A Guide to Latin Dates and Numbers

The Roman Calendar in Brief

The original Roman calendar was 304 days long and had ten months. The year began on March 1, after a blank period of Winter which lay between December and March. These days had no special name, but they helped to keep the calendar in synchronization with celestial events such as the solstices and equinoxes. January and February were added, as the last and the first months respectively, in 713 B.C. The new calendar was 355 days long, with a leap year every other year.

The Roman Republican calendar, adopted in 600 B.C., lengthened the year to 365 days, 355 of which were assigned to the twelve months and ten to a special adjustment period called the "Intercalia", which began on Febuary 24. Eventually, the interval was eliminated and the days added to the months; this reform, set into place during the brief reign of Julius Caesar, was known as the Julian Calendar.

The Julian calendar proved to be out of sync with the real movement of the earth in the cosmos, so in 1582 Gregory XIII issued an edict that called for 10 days to be skipped that October. Catholics immediately adopted the improved calendar, but Protestant and Orthodox countries put their enmity with the Roman See above accuracy and practicality and did not adopt the revision until later. England and America made the leap in 1752. The last European country to adopt the Gregorian calendar was Greece, in 1923.

Dates on European tombs can be expected to conform to either the Julian or the Gregorian calendar.

Latin Months

Special named days of the month include the ides or idus (the 15th of March, May, July, and October; the 13th of all other months), the calends or Kalendae (the first of each month), the nones or Nonae (the 7th day in March, May, July, and October; the 5th of all other months), and the punctum temporis (leap year's day).

Latin Days

Roman Numerals

Latin numbers are constructed from the following set of characters:

Numbers between these values are created through either additive or subtractive notation.

In additive notation, symbols of lesser value follow symbols of higher value. So:

In subtractive notation, a single symbol of a lower value precedes one of higher value. Four is really "one from five", for example. Here are some other examples:

These rules must be followed, too:

1. Symbols may be repeated no more than three times in sequence. So, III is permissible; IIII is not. (Stonecutters sometimes ignore this rule.)
2. Only one symbol of lesser value may be placed before another symbol of higher value, e.g. IV (4) but not IIV (3).
3. The symbols V, L, and D are never subtracted.

Here are a few years rendered in Roman numerals to give you a feel for how it works: