Monday, 8 August 2005

Julius Caesar and his Calendar

In 45 BC Julius Caesar decreed a new calendar, based on the 365-da year as calculated by Sosigenes of Alexandria. However, Sosigenes's year had an extra quarter of a day to it so he cleverly added an extra day in the end of February for every fourth year, which was called bis-secto-kalendae. Caesar, via the Senate, also changed the name of the month of Quintilis to 'July' (in later years the month of Sextilis was renamed 'August' in order to honour Augustus).

In the 4th century AD Constantine the Great added the seven-day week to the calendar (he was inspired by the book of Genesis), while in 1582 Pope Gregory XIII adjusted the calendar, so it was from then on known as the Gregorian calendar.

5 comments:

Ginger Mick said...

Alterior
"Fascinating History' = fascinating blog. I love it. Keep it up.

Alterior said...

Oh, thank you so much! :-)))))

Keith said...

As a child the calendar drove me nuts. Why weren't Sept, Oct, Nov, and Dec the months #7-10? Anyway, great blog

ilya said...

That's because the New Year in Roman times was in March so September was the 7th month.

So before the 7-day week what did they have?

James O said...

On a related point, the Julian calender was used in Russia until 1918 - leading to the fact that the February revolution of 1917 took place in March, and the October Revolution began on the 6th November, by the Western calender.