The Tatharian Calendar (TC) is the civil calendar of the Tatharian Empire and the dominant system of timekeeping across western Rolara. It was standardized by Icaghor, founder of Tatharia Regnum, as a unification of the various religious and regional calendars used by the component cultures of the Tathar valley. The calendar’s epoch, Year 1 TC, marks the formal act of calendrical standardization (the “Year of Law”), not the founding of the Regnum itself, which predates the calendar by several centuries.

Epoch and Conversion

Year 1 TC corresponds to approximately 1124 PE (Post-Extinguishment) in the Ordo Stellae Potentiae. The canonical conversion is:

PE - 1123 = TC

Year 400 TC corresponds to 1523 PE, and Year 409 TC (the current year) corresponds to 1532 PE. The Tatharian Calendar postdates the founding of Tatharia Regnum (c. 400 PE, when Icaghor accepted the crown) by several centuries, and the inaugural Bellatorius Ferox Torneamentum followed it in Year 4 TC (1127 PE). Events predating the calendar’s standardization are retroactively assigned TC dates using the conversion above, producing negative TC values for the earliest periods of Tathar history.

Structure

Year

A standard year contains 360 days across twelve regular months of 30 days each, plus one intercalary month (Bellatorius) that appears only in leap years.

Months

Ordinal Name Abbreviation Days Notes
1 Dracones Dra 30
2 Aranea Ara 30
3 Orcus Orc 30
4 Lotus Primus Pri 30
5 Transgressus Gladios Gla 30
6 Venatio Ven 30
7 Bellatorius Bel 0 (4 in leap years) Intercalary
8 Nautae Vae NaV 30
9 Rotam Rot 30
10 Imperiatrix Quietem Imp 30
11 Lotus Secundus Sec 30
12 Horarium Hor 30
13 Spiritus Spi 30

Bellatorius is an intercalary month inserted between Venatio and Nautae Vae. In non-leap years it has zero days and is effectively absent from the calendar. In leap years (every four years, beginning from Year 0), it contains four days. The month is named for the Bellatorius Ferox Torneamentum, the empire’s gladiatorial tradition. The four days keep the calendar in step with the solar year of 361 days: the 360-day calendar falls one day behind the sun each year, and Bellatorius restores the four days every fourth year. Bellatorius falls at midsummer, and in leap years the summer solstice lands on its last day.

Weeks

The Tatharian week consists of ten days, so each 30-day month holds exactly three weeks, known as Platinum, Crystal, and Queen. The day names run on continuously from one month to the next and through the days of Bellatorius, so a month does not always open on Alesud: every month of 409 TC opens on Banorud. The days are:

Ordinal Name Abbreviation
1 Alesud Ale.
2 Elud Elu.
3 Banorud Ban.
4 Ketenud Ket.
5 Zixud Zix.
6 Akkud Akk.
7 Keraud Ker.
8 Sardud Sar.
9 Tiamud Tia.
10 Bahamud Bah.

Several day names derive from deities in the Pantheobule: Ketenud from Ketenem, Tiamud from Tiamat, and Bahamud from Bahamut.

Seasons

Season Start End
Winter Horarium (month 12) Orcus (month 3)
Spring Orcus (month 3) Venatio (month 6)
Summer Venatio (month 6) Rotam (month 9)
Autumn Rotam (month 9) Horarium (month 12)

These are civil seasons, which open a month or more before the solstice or equinox each one contains. The winter solstice, the longest night of the year, falls on 1 Dracones or within the three days after it, so the year opens at midwinter; in Year 1 TC, the Year of Law, it fell on 1 Dracones itself. The spring and autumn equinoxes fall within the first four days of Lotus Primus and Lotus Secundus, so each of the two Lotus months, the calendar’s months of renewal, opens at an equinox. The summer solstice falls within the first three days of Nautae Vae, or on the last day of Bellatorius in leap years.

Timekeeping

The day is divided into 24 hours, each hour into 60 minutes, and each minute into 60 seconds.

Celestial Bodies

Three celestial bodies are tracked against the Tatharian Calendar.

Luna completes a 29-day cycle through eight phases (New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, Waning Crescent). The single-day phases (New, First Quarter, Full, Last Quarter) each last one day; the transitional phases last six days each, except the waning gibbous, which lasts seven. Luna and Moonwilde share a new moon anchor on Venatio 5, 409 TC.

Moonwilde follows a rapid 13-day cycle through the same eight phases, with transitional phases lasting two days each, except the waning gibbous, which lasts three.

The dark moon, the Binary Planet, visible since 409 TC, follows a cycle of 99 days, with transitional phases lasting 23 or 24 days. It circles Rolara backward, against the course of Luna and the Moonwilde, so it drifts westward through the constellations and rises about a quarter of an hour earlier each night, where Luna rises later. Its first new moon in the current era occurred on Horarium 1, 409 TC.

All three bodies are new on the same day once every 37,323 days, about 103 years. The next such day falls on Spiritus 7, 444 TC. Reckoned backward, the last would have been Nautae Vae 18, 341 TC, before the dark moon appeared in the sky.

Historical Context

The standardization of the Tatharian Calendar was one of Icaghor’s acts of political consolidation. Before its adoption, the diverse kingdoms and tribes of the Tathar valley maintained their own calendars, many tied to the religious observances of the faiths that would later be organized under the Pantheobule. The new calendar merged these systems into a single civil framework, facilitating trade, governance, and record-keeping across the growing Regnum.

For a narrative account of the calendar’s creation and cultural significance, see the in-world document Tatharian Calendar.

Date Format

Dates are conventionally written as: [Weekday], [Day] [Month], [Year] TC

Example: Ketenud, 2 Lotus Secundus, 409 TC.