The calendar used today is based on the ancient Roman system of measuring time and dates. The modern calendar is far simpler than the Roman one. We group the years as AD, which stands for Anno Domini, the year of our lord, and BC, Before Christ. The years are numbered within these two groups. The numbers go backward from BC and forward from AD. The Roman year, like ours, had 365 days, and every fourth year was a leap year after Julius Caesar and his nephew Augustus had reorganized the calendar. The year was also divided into 12 months like ours. The names of our months come from the Roman names. Before Caesar changed the calendar, the Roman year began in March, and February was the last month.

Janarius: January, was named for the god Janus.

Februarius: February, was the month of purification, from the verb februare to purify.

Martius: March, was named for the god Mars.

Aprilis: April, the month of new growth, came from aperio, which means to open.

Maius: May came from the word maius, meaning larger, since it is the month in which the plants grow.

Junius: June was named for the goddess Juno.

Julius: July, named for Julius Caesar, who had birthday in that month.

Augustus: August, named in honor of the Emperor Augustus.

Septimus: September, Octavus: October, Nonus: November, and Decimus: December mean seventh, eighth, ninth, and tenth.

The monthly calendar of the Romans was extremely complicated. Each month had three special days in it. The saying that warned Julius Caesar to “beware of the Ides of March” was referring to March 15. The Ides, the day of the full moon, fell on the 13th of every month except March, July, and October. During those months, they fell on the 15th. The Calends, which comes from a word meaning announce, were the first days of the month. On the first day of each month the high priest announced the religious festivals that would take place during the month. The Nones were between the alends and the Ides and fell on the ninth day before the Ides. The other days were figured backward from those three points, counting both the first day and the last. March 3, for example, would be called the fifth day before the Nones of March. The ides and the Nnes changed in certain months, which made this more complicated. March 16 would be the 17th day before the calends of April, and so forth. During the time of Augustus, great stone calendars were put up at important crossroads and at corners, used to help the average citizen figure out the date.