Maya Civilization

The Maya Calendar System

The Maya calendar system is not a single instrument but an interlocking suite of counts, almanacs, and astronomical tables that together allowed daykeepers, scribes, and rulers to mark time from a fraction of a day to hundreds of millions of years into the past and future. At its core stood three interlocking cycles — the 260-day Tzolkin sacred almanac, the 365-day Haab’ solar year, and the Long Count that placed every day inside a strictly cumulative count of days from a mythological creation epoch. Layered onto these were the astronomical cycles tracked in the surviving books: the 584-day cycle of Venus, the 780-day cycle of Mars, lunar tables, and the eclipse prediction tables of the Dresden Codex. No other pre-Columbian civilization in the Americas developed a calendrical apparatus of comparable depth, and few in the world matched its precision.

This page surveys the system as a whole, traces the way its components were combined in practice, and explains the role of the ritual specialist — the ah k’in, “daykeeper” or “he of the sun” — who interpreted the almanacs for communities across the Maya lowlands and highlands.

The interlocking cycles at a glance

The three principal counts are not interchangeable; each answered a different question.

The Tzolkin answered “what kind of day is it?” It is a 260-day cycle formed by permuting thirteen numerical coefficients (1 through 13) against twenty named day signs (Imix, Ik’, Ak’bal, K’an, Chikchan, Kimi, Manik’, Lamat, Muluk, Ok, Chuwen, Eb, Ben, Hix, Men, K’ib, Kab’an, Etz’nab, Kawak, Ajaw). Because 13 and 20 share no common factor below 260, the same name-and-number pair — for example, 1 Ajaw, the most sacred seat in the cycle — repeats only once every 260 days. The Tzolk’in functioned as a divinatory almanac; the principals of Maya religion and cosmology such as the Hero Twins and the Maize God were tied to specific positions within it.

The Haab’ answered “what time of year is it?” It is a 365-day approximation of the tropical year built from eighteen named months of twenty days each (Pop, Wo, Sip, Sotz’, Sek, Xul, Yaxkin, Mol, Ch’en, Yax, Sak, Kej, Mak, K’ank’in, Muwan, Pax, K’ayab, Kumk’u) followed by a five-day period called Uayeb. The Haab’ tracked agricultural seasons, market cycles, and the timing of festivals tied to solstices and equinoxes.

The Long Count answered “how many days have passed since the zero date?” Every inscription in the Classic period carries a five-place base-20 (with one base-18 exception) count: kin (1 day), uinal (20 days), tun (360 days), katun (7,200 days), and baktun (144,000 days). The base date from which Long Count days are reckoned is 4 Ajaw 8 Kumk’u, equivalent (in the most widely used GMT correlation) to 11 or 13 August 3114 BCE in the proleptic Julian calendar.

A fourth construct, the Calendar Round, combined any given Haab’ day with any given Tzolk’in day. Since 260 and 365 share a least common multiple of 18,980 days (roughly 52 solar years), the same combined Calendar Round position — for example, 4 Ajaw 8 Kumk’u — repeats only once every 52 years. A person born on a particular Calendar Round day would not see that exact combination again in their adult life, and so such days were treated as omens of weight.

A working example: 4 Ajaw 8 Kumk’u

The single most famous day in the entire Maya calendar is 4 Ajaw 8 Kumk’u. In the Long Count it is written 13.0.0.0.0 — thirteen baktuns, zero katuns, zero tuns, zero uinals, zero kins — the day on which, according to Maya creation mythology, the present world was set in order after three previous creations had been destroyed. Every subsequent Long Count date can be expressed as the number of days elapsed since 4 Ajaw 8 Kumk’u, and every baktun-ending (positions such as 9.0.0.0.0, 10.0.0.0.0, 11.0.0.0.0, 12.0.0.0.0, 13.0.0.0.0) marks the close of a 144,000-day cycle that Classic-period kings treated as politically significant.

The 13-baktun cycle itself is a count of 1,872,000 days — 5,125.37 tropical years — and its completion on what the correlation problem places at 21 December 2012 became the source of the so-called “2012 prophecy,” discussed in detail on What did the Maya 2012 prophecy actually say?.

How the counts were used together

In a Classic-period inscription, a single date is typically given in three ways: as a Long Count (for absolute chronology), as a Calendar Round (for ritual and seasonal placement), and as a “half-k’atun” or “k’atun-ending” modifier (for political ceremony). Stela C at Quiriguá famously records a 9-baktun ending in the reign of K’ahk’ Tiliw Chan Yopaat (Cauac Sky, AD 724–785), and Tikal’s Stela 9 carries the baktun-9 completion of 13.0.0.0.0’s distant echo at 9.0.0.0.0 — equivalent to AD 435 in the GMT correlation, the moment when the dynasty of Yax Ehb’ Xook, founded centuries earlier in the Preclassic, was retroactively celebrated as having been inaugurated at the close of a prior world age.

A daykeeper consulting his almanac on a given Calendar Round day would cross-reference the Tzolk’in position with entries in a k’al (counting) book, check the position of Venus in its 584-day cycle if an elite ceremony were being planned, and verify whether the day fell inside a predicted eclipse window. Such layering produced recommendations ranging from “unremarkable, fit for market” to “dangerous, abstain from travel.” The result is a system that looks at first glance like a numerological curiosity but in practice functioned as a sophisticated scheduling technology for ritual, agriculture, and politics.

The 52-year Calendar Round cycle

Because 260 and 365 share no common factor below 18,980 days, the same combined Calendar Round position recurs only once every 52 Haab’ years. The 18,980-day cycle is not a named “century” in the European sense; the Maya spoke of k’atun-endings and baktun-endings, not Calendar Round completions. Yet a 52-year cycle is documented ethnohistorically: highland and lowland communities feared the closing days of such a cycle, fearing that a Calendar Round completion could presage the end of the world. The Spanish chronicler Bernardino de Sahagún, working among the Nahua but drawing on Mesoamerican-wide traditions, recorded parallel anxieties that survived in the late sixteenth century.

In the colonial and modern K’iche’ and Kaqchikel highlands, this 52-year fear is closely related to the New Fire ceremony — although the Aztec New Fire ceremony (a Central Mexican rite documented at the close of a 52-year xiuhmolpilli in 1507) is sometimes mistakenly attributed to the Maya. The Maya did perform analogous period-renewal rites at katun endings, but the Aztec 52-year Binding of the Years is a distinct tradition, and the use of that label in popular sources for the Maya case is anachronistic.

The katun, the tun, and political time

Of all Maya period units, the katun — 7,200 days, or roughly 19.7 tropical years — was the most politically charged. K’atun-endings (k’atun b’ate’) were marked by monuments, by the accession ceremonies of new rulers, and by the burning of k’atun books — prophetic almanacs kept by the k’atun-b’atab’ (the katun-keeper) that gave a particular katun its character and predicted events to come. The Books of Chilam Balam, colonial-era Yucatec compilations drawing on older Cholan and Yucatecan sources, record the names of the katuns in a recurring sequence: k’atun 13 Ajaw, k’atun 11 Ajaw, k’atun 9 Ajaw, and so on, alternating with their counterparts.

In the Terminal Classic period (roughly AD 800–950), a 13-katun span, the collapse of the Classic Maya court system coincided with the close of 10.0.0.0.0 (AD 830 in the GMT correlation), a moment commemorated across the southern lowlands. Some inscriptions are explicit about this: Dos Pilas, Aguateca, and Cancuén record a sharp uptick in warfare at 10.0.0.0.0 and immediately afterward.

The 819-day cycle

Less well known outside specialist literature, the 819-day cycle is a count that appears in the Late Classic inscriptions of Caracol and a handful of other sites. Its mathematical structure — 819 = 7 × 117 = 9 × 91 = 13 × 63 = 3 × 273 — intermeshes neatly with the 260-day Tzolk’in (because 819 = 3 × 260 + 39, with the 39 being a small correction), the 585-day synodic period of Venus, the 780-day Mars cycle, and the 9-day cycle of the lords of the night. John Linden and Victoria Bricker, building on epigraphic work by David Stuart, have argued that the 819-day count functioned as a higher-level tonal harmonic — a way of rotating through the four cardinal colors and the four cardinal directions in a single super-cycle. The 819-day period is rare in monumental inscriptions but unmistakable at Caracol, where the k’atun markers of the dynasty are sometimes given with explicit 819-day co-efficients.

Venus, the “star wars” cycle

The planet Venus — alternately the Morning Star and the Evening Star over a 584-day cycle — was tracked with extraordinary care in the Dresden Codex Venus Table, which records eight cycles of 584 days plus corrections (an 8 × 584 = 4,672-day span corresponding to roughly 146 Haab’ months). The Dresden Venus table allowed daykeepers to predict, to within a day, when Venus would reappear as Morning Star after superior conjunction, and when it would reach greatest brilliancy. The table is paired with a Venus almanac tied to warfare and sacrifice: first-station Venus was a dangerous time, suitable for capturing prisoners, and the inscriptions of Copán and Quiriguá record kings timing their accession rites to the heliacal rising of Venus.

The 584-day Venus cycle is also tied to the Lunar Series found in Classic-period monuments, a 6- or 9-lunation block recording the age of the moon, the lunar month number, and a “lunar belt” glyph, all of which let epigraphers reconstruct the exact date a stela was erected.

The eclipse tables and lunar arithmetic

The Dresden Codex contains, in addition to its Venus and Mars tables, an eclipse prediction table covering 405 lunar months — 11,960 days, or about 32.75 tropical years. The structure is built on the fact that 405 lunations ≈ 46 eclipse half-years, so the table returns to the same eclipse possibility every 405 months. The table can be cross-checked against the historical record of eclipses visible from the Maya area between roughly AD 700 and 730, and it predicts eclipses to within a day of the actual event. Whether the table was ever used to schedule real-world defensive action during eclipses is debated, but the table is independent proof of the precision of Maya astronomy.

Zenith-passage days and architectural alignments

A particularly practical use of the calendar was the observation of zenith-passage days, when the sun passed directly overhead at local noon and vertical sticks cast no shadow. Zenith passage at Copán occurs on 30 April and 13 August; at Tikal on 23 May and 12 August; at Chichen Itza on 20 May and 22 July. The interval between the two passages defines the agricultural year, and the 260-day Tzolk’in is sometimes argued to have been calibrated to these observations. More directly, the E-Group architectural complexes — the famous radial pyramids at Uaxactún, Tikal, and Copán — frame sunrise on the equinoxes and zenith-passage days from a viewing platform. The Caracol observatory at Chichen Itza, with its surviving upper windows, framed Venus and other planets on key dates in their cycles, an example of temple astronomical alignment at its most ambitious.

Mars, Jupiter, and Saturn

Although Venus dominates the surviving astronomical tables, the Dresden Codex preserves a separate Mars table (with 780-day cycles), and the Madrid Codex contains almanacs relating to Jupiter’s synodic period (398.88 days) and Saturn’s (378.09 days). The Classic-period inscriptions rarely mention these planets explicitly, but their cycles are implied by almanac structure and by the Lords of the Night sequence (a 9-day cycle of “G” glyphs that rotates in a fixed order, with the 9 × 819-day expansion matching the four cardinals and four colors). Whether the daykeepers also tracked stars such as Capella, the Pleiades, and Orion’s Belt is the subject of ongoing research; alignments to the Pleiades in the 260-day cycle are documented at Chichen Itza and possibly at Xochicalco.

The 2012 phenomenon and its actual contents

The completion of the thirteenth baktun, on what the GMT correlation places at 21 December 2012, has been the subject of a global popular phenomenon. Modern academic Maya scholarship, summed up in the work of scholars such as David Stuart, Stephen Houston, and the ADEQ (Acuerdo para el Desarrollo Económico y Social de los Pueblos Maya) consultative group, is unanimous that no Classic Maya inscription predicts the end of the world at that moment. The baktun-13 completion is, rather, simply the close of a 1,872,000-day cycle after which a new 13-baktun count would have begun — comparable to the rollover of an odometer. The Tortuguero inscription (Monument 6) is the most explicit contemporaneous text on the rollover and refers to bolon yookte — a contested term sometimes read as “the legitimate gods will be installed” — without apocalyptic content. The detailed scholarly reading of these texts is laid out in What did the Maya 2012 prophecy actually say?.

The daykeeper: the ah k’in

The specialist who maintained and interpreted the almanacs was the ah k’in, literally “he of the sun” or “he of the day.” The ah k’in combined the role of priest, calendar-keeper, diviner, and (in the colonial era) community teacher of the Christian calendar. In the highland K’iche’ and Kaqchikel communities documented in the sixteenth and seventeenth centuries, the ah k’in kept a wooden board on which 260 days of the Tzolk’in were marked, with seeds or sticks for the day counts; this practice survived into the twentieth century in some villages of highland Guatemala. The ah k’in in Classic-period inscriptions is shown on Bonampak murals and on carved panels at Palenque performing bloodletting and almanac-reading rituals for the king.

The ritual year turned on the ah k’in’s advice: he selected the day for planting, the day for marriage, the day for the king’s accession, and the day for warfare. He was paid in cacao, cloth, and other Maya trade goods and held a hereditary office in many communities, with a corresponding office of ch’ok ah k’in (apprentice daykeeper) learning the almanacs in parallel.

The role of the Long Count inscriptions

The Long Count was not just an abstract mathematical framework; it was the medium in which Classic-period royal memory was committed to stone. Stelae from the Petexbatun region, from Tikal, from Copán, from Quiriguá, from Palenque, from Calakmul, and from over a hundred other sites record a Long Count position followed by a Calendar Round position, an “is-to-be” clause (uhtiiy), and an “arrival” or “passage” verb identifying the named event. About 15,000 surviving carved inscriptions have been catalogued by epigraphers, and the vast majority carry Long Count dates — making the Long Count the single most common text type in Maya writing.

This consistency is the basis of the modern Maya historical chronology, which can locate almost every documented Late Classic ruler within a few years of an absolute date. The precision of the inscriptions is such that a king whose Stela records an accession on 9.9.2.4.8 (3 Lamat 6 Mol) can be tied to a Calendar Round day corresponding to AD 658, and the war he fought that year, recorded in the annals glyphic passages, can be matched to events in Tikal’s dynastic history.

The Calendar Round and the 52-year cycle revisited

The Calendar Round is the Calendar that ordinary people lived by; the Long Count is the one that kings used to enshrine their accessions and the daykeepers used to mark katun-endings. A 52 Haab’-year period — 18,980 days — was the time after which a given Calendar Round combination would recur. The 18,980-day cycle did not structure political life directly, but it did structure ritual life: parents remembered the day-sign of a child’s birth, and the day-sign returned 52 Haab’-years later, when the parent or grandparent was near death. A 52-year completion was a moment of reckoning, when an old man or woman would see their child’s day-sign return, and the daykeeper would read the almanac to determine what that return meant for the family.

The role of the five named day-periods

In the colonial highland calendar, the 260-day cycle was subdivided into 20 named 13-day periods called trecenas (sometimes ch’ol k’ij “the keepers of the days” in the highland tradition) and into 13 named 20-day periods called veyenes in the early colonial Yucatec sources. Each trecena and each veyene had a presiding spirit, a glyph, a set of prognostications, and a corresponding almanac page in the books. The Chilam Balam books preserve some of these prognostications in Yucatec Maya; the early colonial Testerian manuscripts preserve others in Nahuatl and Spanish transliterations.

The trecenas are particularly important in the almanac tradition: the 1st of any month begins a new trecena, and the 13 day-signs of that trecena are read as a sequence of omens, with the K’ib’ (representing the 4th day in some almanacs, the 5th in others) and the Ajaw (the 13th and 20th, the most sacred position) bearing the principal messages.

The 819-day cycle and the 4-color rotation

Linden and Bricker have argued that the 819-day cycle — 819 = 7 × 117 = 9 × 91 = 13 × 63 = 3 × 273 — encodes a four-color, four-direction, and four-cardinal cosmological rotation. Each 819-day block passes through a complete cycle of the Lords of the Night (9-day cycle × 91 = 819), through a complete cycle of the 13-day trecena coefficient, and through 3.15 cycles of the 260-day Tzolk’in. The 819-day cycle, if their reading is correct, was a “super-Tzolk’in” used to coordinate the four-color, four-direction cosmological frame that runs throughout Maya religion and cosmology.

A note on correlation constants

Most of the absolute dates given in this article assume the Goodman-Martinez-Thompson (GMT) correlation constant of 584,283 (the Spinden correlation was 489,384; the modified GMT of 584,285 has been used in some astronomical work). The difference is roughly 260 days, so a date given as 21 December 2012 in GMT becomes 14 December 2012 in Spinden. The 260-day shift means that the Venus cycle, eclipse cycle, and lunar series all align slightly differently under the two correlations; the choice between them is one of the most consequential issues in Maya astronomy, with the modern academic consensus strongly favoring the GMT correlation on the basis of the lunar tables in the Dresden Codex.

The Tzolk’in and the divinatory year

Within the 260-day Tzolk’in, the 13 trecenas of 20 days each (some almanacs organize by 20 veyenes of 13 days) carry a rich body of omens. The 20 day-names are not just labels; they are spirits with attributes: Imix is the water-lily, the primordial pond; Ik’ is wind, breath, the life force; Ak’bal is darkness, the house of night; K’an is the yellow maize ear, abundance; Chikchan is the serpent-sky, the celestial snake; Kimi is death; Manik’ is the deer, the hunter’s hand; Lamat is the rabbit, the planet Venus; Muluk is the water, the rains; Ok is the dog, the storm; Chuwen is the monkey, the trickster-artisan; Eb’ is the road, the rough path; Ben is the reed, the cosmic axis; Hix is the jaguar; Men is the moon, the elder of the sky; K’ib’ is the vulture, the transformed soul; Kab’an is the earth, the earthquake; Etz’nab’ is the flint, the mirror; Kawak is the storm, the K’awill; Ajaw is the lord, the sun, the king.

A daykeeper reading a child’s birth on, say, 8 Ajaw, would consult the Ajaw almanac and learn that the child carried the sign of the lord; he would note that Ajaw is the patron of kings, the day on which Classic-period rulers took office, the day on which the Hero Twins are said to have ascended to the sky to become the sun and the moon. He would then advise the parents on a corresponding name, a corresponding day for the binding ceremony, and a corresponding fate.

The Haab’ months and the agricultural year

The 19 months of the Haab’ (18 of 20 days plus 5-day Uayeb) are tied to agricultural seasons. Pop, the first month, is the time of sowing; Yax, the tenth, is the first green of the maize; Sek, the fifth, is the ripening of the bean; K’ayab, the seventeenth, is the dry time before harvest. The five days of Uayeb are the dangerous time outside the year, when the spirits roam and the year-boundaries are sealed. The Uayeb was a time of fasting and ritual abstention, with no marriages, no business, and no travel.

The relationship to Mesoamerican calendars

The Maya calendar shares structural features with the calendars of Mesoamerican civilizations generally, including the 260-day sacred almanac, the 365-day vague year, the 52-year cycle, and the use of the day-name Cipactli in some highland groups. The Zapotec, Mixtec, and Aztec all used variants of the 260-day calendar; the 365-day year is also universal in Mesoamerica. The Maya Long Count, however, is unique to the Maya region: it is a cumulative day count of a kind not used in Central Mexico, where the xiuhmolpilli (52-year cycle) and the Calendar of Tonalpahualli (260-day almanac) are the dominant structures.

The day-name 4 Ajaw and the creation

The day-name 4 Ajaw (the fourth appearance of Ajaw in a 260-day cycle) is the seat of the present creation. The creation narrative recorded on Quiriguá Stela C, on Tikal’s Temple of the Inscriptions’ contemporary texts, and in the Books of Chilam Balam places 4 Ajaw 8 Kumk’u at the moment when, after three previous creations had failed, the gods set the present world in place. The 13-baktun completion is, in this reckoning, the day 13.0.0.0.0 4 Ajaw 8 Kumk’u — exactly the same Calendar Round position as the base date. The rollover is, in other words, not an end of the world but a return to the original moment of creation, after which the count would begin again at 0.0.0.0.0 4 Ajaw 8 Kumk’u.

The katun prophecies in the Books of Chilam Balam

The colonial-era Books of Chilam Balam, written in Yucatec Maya with Spanish orthography, preserve a sequence of katun prophecies attributed to the prophet Chilam Balam of Maní. Each katun of the 13-katun cycle is named (13 Ajaw, 11 Ajaw, 9 Ajaw, 7 Ajaw, 5 Ajaw, 3 Ajaw, 1 Ajaw, 12 Ajaw, 10 Ajaw, 8 Ajaw, 6 Ajaw, 4 Ajaw, 2 Ajaw) and given a character: 8 Ajaw, the katun that began in 1618 and was the “katun of the book,” is a time of pestilence and migration; 4 Ajaw, “the katun of battles”; 6 Ajaw, “the katun of foreigners.” These are not predictions in the modern sense; they are retrospective readings of the recent past in the katun framework, set down after the events they describe.

A note on modern survivals

In the highland communities of Guatemala, the Tzolk’in remains in continuous ritual use among Q’eqchi’, K’iche’, Kaqchikel, Mam, and Tz’utujil daykeepers (called aj q’ij in modern K’iche’), and the aj q’ij continues to select the day for marriages, planting, and naming ceremonies. The Haab’ is much less commonly used in modern practice, although the 365-day vague year is still sometimes noted in the highland communities. The Long Count is no longer in continuous use, but it is maintained in the modern Guatemalan Maya calendar reform movement led by the Oxlajuj Ajpop group and recognized by the Guatemalan government in 2011 (the “Mayan New Year” is celebrated on the baktun-13 completion 13.0.0.0.0, falling on 13 December in the Spinden correlation or 21 December in the GMT correlation).

The calendar as a cultural system

The Maya calendar is not a tool for telling time; it is a cultural system that links astronomy, agriculture, ritual, and political life. To understand the Classic Maya court is to understand a state that, in the words of epigrapher David Stuart, “ran on the calendar” — that scheduled the planting, the accession, the war, the dedication of the temple, and the bloodletting of the king against the position of Venus, the day of the Tzolk’in, the month of the Haab’, and the count of the Long Count. The surviving Maya codices — the Dresden, Madrid, Paris, Grolier, and the few fragments of the lost books of the post-conquest — are the almanacs, the Venus tables, the eclipse tables, and the Maya mathematical tables of this system, and they remain the densest surviving record of pre-Columbian Maya science, mathematics, and astronomy.

The origin and antiquity of the 260-day cycle

The 260-day Tzolkin is attested in the archaeological record from the Middle to Late Preclassic (c. 600–400 BCE), with the earliest unambiguous examples coming from the Isthmian script of the Gulf Coast and from the early Maya lowlands. The earliest Long Count date in the Maya area is 7.16.3.2.13, recorded on Stela 2 of Chiapa de Corzo, Mexico, c. 36 BCE, although earlier Long Count dates from the Isthmian area (notably Tres Zapotes Stela C, c. 32 BCE) suggest that the system was in use in the broader Mesoamerican area before the Classic period. The 260-day almanac appears in even earlier contexts: the San Bartolo murals (c. 300 BCE) include glyphs that are widely read as 260-day cycle markers, and the Takalik Abaj Stela 2 (c. 1st century BCE) carries an early Long Count.

The deep antiquity of the 260-day cycle is paralleled by its breadth. The cycle appears in Olmec, Zapotec, Mixtec, Aztec, and Maya contexts, with very similar (though not identical) day-name sequences. The pan-Mesoamerican character of the cycle suggests a common origin in the Middle Preclassic, with the divergence in the day-names reflecting local ritual traditions. The 20-day month sequence is similarly widespread, and the 365-day Haab’ is attested in Olmec contexts as early as c. 900 BCE.

The Long Count is, by contrast, specifically Maya. The earliest Long Count inscriptions come from the Maya lowlands and the Isthmian area in the Late Preclassic, and the system is not attested outside the Maya area in the same form. The 360-day tun, the 7,200-day katun, the 144,000-day baktun, and the 4 Ajaw 8 Kumk’u base date are unique to the Maya tradition, and they are the basis of the most elaborate day-count of any pre-Columbian civilization.

The 18,980-day Calendar Round and the New Fire

The 18,980-day Calendar Round is the smallest cycle after which a given combined Tzolkin-Haab’ position recurs exactly. The cycle is documented ethnohistorically as a time of ritual renewal in both the Maya and the Aztec traditions, with the Aztec New Fire ceremony (Toxilhuitl) being the best-documented example. The Maya equivalent is preserved in the Books of Chilam Balam and in modern highland K’iche’ ritual.

The 18,980-day cycle is 73 × 260 = 18,980 (i.e., 73 complete Tzolkin cycles) and 52 × 365 = 18,980 (i.e., 52 complete Haab’ years). The cycle is also 18,980 ÷ 360 = 52.72 (i.e., 52 complete 360-day tuns plus 260 days), and it is the basis of the 52-year cycle in Mesoamerican ritual life.

The 52-year cycle was, in the Aztec tradition, the time between successive New Fire ceremonies. The ceremony, held at the close of a 52-year cycle, involved the extinction of all fires in the city, the lighting of a new fire on the chest of a sacrificed captive, and the carrying of the new fire to the temples and houses of the city. The ceremony is documented in the Florentine Codex of Bernardino de Sahagún and in the colonial-era Aztec sources.

The Maya equivalent of the New Fire ceremony is less well documented, but it is preserved in the Chilam Balam books and in modern highland K’iche’ practice. The highland aj q’ij mark the close of a 52-year cycle with a ritual extinguishing of fires and the lighting of a new fire, although the practice is now syncretized with the Christian calendar. The 18,980-day cycle is, in this respect, a pan-Mesoamerican institution, with the Maya and the Aztec traditions sharing the basic structure but differing in the details.

The 360-day tun and the 365-day Haab’

The 360-day tun of the Long Count is shorter than the 365-day Haab’ by 5 days. The 360-day tun is a useful approximation for the Long Count, and the 18-month structure of the Haab’ (18 × 20 = 360) is reflected in the tun’s 18 × 20 = 360-day length. The tun is the basis of the katun (20 tuns = 7,200 days) and the baktun (20 katuns = 144,000 days), and the tun is the Long Count’s “year.”

The 360-day tun is not the only unit of the Long Count; the uinal (20 days) is the Long Count’s “month,” and the kin (1 day) is the Long Count’s “day.” The 5-day difference between the 360-day tun and the 365-day Haab’ is corrected in the astronomical tables, with the daykeepers using the 365-day Haab’ for the solar year and the 360-day tun for the Long Count.

The 360-day tun may be derived from the 18-month Haab’, with the 18 × 20 = 360 days being the “Haab’ year” minus the 5-day Uayeb. The 360-day tun is, in this respect, an “abstract” year that is tied to the Haab’ structure, and the daykeepers used the tun as a way of organizing the Long Count without tying it to the solar year. The tun is, however, an approximation, and the daykeepers used the astronomical tables to keep the tun and the Haab’ in agreement with the actual tropical year.

The 9-day Lords of the Night and the calendar

The Lords of the Night (also called the G glyphs or the Bolon Dzacab in some sources) are a 9-day cycle attested in the Classic-period inscriptions from the Late Preclassic onward. The 9-day cycle is independent of the Tzolkin and the Haab’, and it is a way of specifying the day in a 9-day rhythm. The Lords of the Night are sometimes interpreted as the patrons of the 9 underworlds in the Maya underworld cosmology, and the 9-day cycle is tied to the 9-day journey of the Hero Twins through Xibalba in the Popol Vuh creation account.

The 9-day cycle is a “side-wheel” of the Maya calendar system, running parallel to the Tzolkin and the Haab’ and the Long Count. A given Long Count day has a single position in each of the four wheels, and the daykeeper would specify the day in all four. The 9-day cycle is, in this respect, a 4-wheel timekeeping system, with each wheel running at its own speed and serving its own purpose.

The 819-day cycle of Caracol and other Late Classic sites returns the 9-day Lord to the same position only after 819 days (819 = 9 × 91), and the 9-day cycle is one of the structures on which the 819-day harmonic is built. The 819-day cycle is sometimes read as a “super-Lords of the Night” that rotates through the 9-day cycle 91 times.

The 4-Ajaw 8-Kumk’u base and the present creation

The 4 Ajaw 8 Kumk’u base date is, in the Maya creation mythology, the day on which the present world was created. The Popol Vuh records three previous creations that were destroyed:

  • The first creation was of mud; the humans dissolved in water.
  • The second creation was of wood; the humans were dry and jointless, and were destroyed by the Xibalba lords in a great flood.
  • The third creation was of maize; the humans were of flesh and blood, but they were imperfect, and the gods had to perfect them.

The fourth creation, the present world, was set in place on 4 Ajaw 8 Kumk’u, with the k’uhul ajaw (the holy lord) as the patron of the day. The 13-baktun cycle is, in this reckoning, the time from the present creation to the 1,872,000-day completion, and the cycle is the basis of the Maya historical periodization. The 13-baktun completion is, in this reckoning, the close of a present world, and a new creation would begin on the next 4 Ajaw 8 Kumk’u day.

The 4 Ajaw 8 Kumk’u base is the most sacred day in the Maya calendar, and every Long Count date is the number of days since this day. The 13-baktun completion 13.0.0.0.0 4 Ajaw 8 Kumk’u is the close of the present world, and a new creation would begin on the next 4 Ajaw 8 Kumk’u day. The 13-baktun cycle is, in this respect, a closed cycle, and the 13-baktun completion is the close of a present world and the beginning of a new one.

The role of the uinal and the kin in the Long Count

The uinal (20 days) and the kin (1 day) are the two smallest units of the Long Count. The uinal is the basis of the Haab’ month, with 18 uinal being the 360-day tun. The kin is the basis of the day-count, and every Long Count date is the number of kin since the base date.

The uinal and the kin are written in the inscriptions with the uinal glyph (a moon glyph) and the kin glyph (a k’in face glyph), with bar-and-dot coefficients. The uinal and kin glyphs are the most common glyphs in the inscriptions, and they are the basis of the Long Count day-count.

The uinal and kin are also tied to the Maya mathematical tradition, with the 20-day uinal being the basis of the vigesimal system. The Maya concept of zero is used in the kin and the uinal positions, with the shell glyph representing 0. The Maya mathematical system is, in this respect, the basis of the Long Count, and the Long Count is the most elaborate application of the Maya mathematical system.

The calendar and the dynastic cycle

The Maya dynasties of the Classic period were tied to the Long Count, with the katun-ending being the moment of dynastic transition. The 9.0.0.0.0 baktun-ending (AD 435) is the moment when the Tikal dynasty is retroactively commemorated as having been founded; the 9.4.0.0.0 katun-ending (AD 514) is the moment when the Copán dynasty is founded by K’inich Yax K’uk’ Mo’; the 9.12.0.0.0 katun-ending (AD 672) is the moment when K’inich Janaab’ Pakal completes the Temple of the Inscriptions at Palenque.

The dynastic cycle of the Classic Maya is, in this respect, tied to the Long Count, and the inscriptions of the Classic period are dominated by katun-endings and baktun-endings. The dynastic cycle of the Maya lowlands is a katun-by-katun narrative, and the modern chronology of the Classic Maya is the basis of the most precise pre-modern chronology in the world.

The collapse and the calendar

The 10.0.0.0.0 baktun-ending (AD 830) is the moment when the southern lowland cities began their long collapse. The collapse is documented in the inscriptions of Dos Pilas, Aguateca, Cancuén, and other Petexbatun sites, with the Petexbatun wars recorded in the inscriptions of the period. The 10.0.0.0.0 baktun-ending is a major event in the Terminal Classic period, and the monuments of the period document a sharp uptick in warfare, drought, and political fragmentation.

The collapse of the southern lowlands is not the end of the Maya civilization; the northern lowlands continue to flourish, and the Postclassic period sees the rise of new centers such as Chichen Itza and Mayapan. The collapse is, however, a major transformation in the Maya civilization, and the calendar of the Terminal Classic period is dominated by the 10.0.0.0.0 baktun-ending and the events that followed it.

The colonial and modern continuation

The Maya calendar system did not disappear with the Spanish conquest. The 260-day Tzolkin continued in the highland K’iche’, Kaqchikel, Tz’utujil, and Q’eqchi’ communities, and the daykeeper (aj q’ij) continues to maintain the almanac. The 365-day Haab’ is less commonly maintained, although the 18-month structure survives in some agricultural rituals. The Long Count was not maintained in the colonial era, although the Books of Chilam Balam preserve the katun names and refer to baktun endings in a post-conquest context.

The modern Maya calendar reform movement is, in this respect, a revival rather than a continuation. The Long Count is now taught in some bilingual schools, and the Mayan New Year is celebrated on the baktun-13 completion 13.0.0.0.0. The modern Maya identity is tied to the calendar, and the calendar is a key element of the modern Maya cultural heritage.

A brief glossary of the calendar

  • Tzolkin — 260-day sacred almanac, the basis of the divinatory year.
  • Haab’ — 365-day solar year, the basis of the agricultural year.
  • Long Count — strictly cumulative day-count from 4 Ajaw 8 Kumk’u, the basis of the absolute chronology.
  • Calendar Round — combined Tzolkin-Haab’ position, the basis of the ritual and seasonal year.
  • Baktun — 144,000 days, the largest standard unit of the Long Count.
  • Katun — 7,200 days, the second-largest unit, the basis of the political year.
  • Tun — 360 days, the Long Count’s “year.”
  • Uinal — 20 days, the Long Count’s “month.”
  • Kin — 1 day, the Long Count’s “day.”
  • 4 Ajaw 8 Kumk’u — the base date, the day of the present creation.
  • Lords of the Night — 9-day cycle, the “side-wheel” of the calendar system.
  • 819-day cycle — Late Classic harmonic, attested at Caracol.
  • Trecena — 13-day period in the Tzolkin.
  • Veyene — 20-day period in the Tzolkin.
  • Uayeb — 5-day period at the end of the Haab’.
  • Ah k’in / aj q’ij — daykeeper, the ritual specialist of the calendar.
  • Lunar Series — 6-lunation block in the inscriptions.
  • Eclipse table — 405-lunar-month almanac in the Dresden Codex.
  • Venus table — 5-page 8-cycle almanac in the Dresden Codex.

Sources

  • Aveni, A. F. (2001). Skywatchers of Ancient Mexico. University of Texas Press. — link
  • Aveni, A. F. & Hartung, H. (1986). Maya city planning and the calendar. Transactions of the American Philosophical Society 76 (1). — link
  • Edmonson, M. S. (1988). The Book of the Year: Middle American Calendar Systems. University of Utah Press. — link
  • Teeple, J. E. (1926). Maya Astronomy. Contributions to American Archaeology No. 2. Carnegie Institution of Washington. — link
  • Rice, P. M. (2007). Maya Calendar Origins: Monuments, Mythohistories, and the Materialization of Time. University of Texas Press. — link
  • Coe, M. D. (1993). The Maya (5th ed.). Thames & Hudson. — link