What's in a date?
Around 4231 BC (experts are don’t agree on the exact date) The Egyptians created a calendar. It consisted of approximately 365 days (again, not everyone agrees here either).
There were three seasons in the calendar that consisted of 120 days each.
Inundation or Flood (Akhet): was from September to January.
Emergence or Winter (Peret): was from January to May.
Low Water or Harvest or Summer (Shemu): was from May to September.
Experts say the Egyptian calendar was separate from the calendar we use today, but you will see why I have included it.
It is thought that around 738BC Romulus, the founder of Rome created the Roman Republican calendar. Each month started and ended with the new moon. So were around 30 or 31 days. This meant the 10 recorded months covered around 304 days.
The calendar consisted of 10 months in a year of 304 days.
The 10 months were named :
Mensis Martius
Month of Mars (god- Martius)
Mensis Aprilis
Month of Aprilis (god- Aprilis)
Mensis Maius
Month of Maius (god - Maia)
Mensis Junius
Month of Lunius (god - Juno)
Mensis Quintilis
Fifth month
Mensis Sextilis
Sixth month
Mensis September
Seventh month
Mensis October
Eight month
Mensis November
Ninth month
Mensis December
Tenth month
The Romans ignored the remaining 61 days which were not important in agriculture, so were just classed as unrecorded winter time.
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Numa Pompilius (753–672 BC. Reigned 715–672 BC) changed the calendar by splitting the unrecorded winter time into January and February. At this point March was still the first month in the year.
Mensis Januarius
Month of Janus (god - Janus)
Mensis Februarius
Month of Februa (festival of Purifications or Purgings)
This calendar had a four year cycle that consisted of 355, 377, 355, 378 days. Which meant the second and fourth year had 27/28 additional days crammed into February.
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In 45 B.C. Julius Caesar ordered a calendar consisting of twelve months based on a solar year.
This calendar employed a cycle of three years of 365 days, followed by a year of 366 days (leap year).
The new changes:
Mensis Quintillis was renamed Mensis Julius (Julius Caesar)
Mensis Sextilis was renamed Mensis Augustus (Augustus)
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The next big change to the calendar was when Pope Gregory XIII 1502 to 1585, Pope: 1572 to 1585) introduced some changes in October 1582.
The days were changed to 365.2425 days, meaning the leap year would only occur once every four years, this was to try to correct the time drift which was changing the equinox days each year. Also to line the equinoxes back up Thursday the 4 October 1582 was immediately followed by Friday 15 October 1582. Effectively cutting out 10 days during the reset.
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In 1750 an Act of Parliament in England was created to change all calendars in England and all of its colonies in 1752.
By that time the discrepancy between a solar year and the Julian Calendar had grown by an additional day, so that the calendar used in England and its colonies was 11 days out-of-sync with the Gregorian Calendar in use in most other parts of Europe.
England's calendar change included three major components. The Julian Calendar was replaced by the Gregorian Calendar, changing the formula for calculating leap years.
The beginning of the legal new year was moved from March 25 to January 1. Finally, 11 days were dropped from the month of September 1752.
The changeover involved a series of steps:
December 31, 1750 was followed by January 1, 1750 (December was still the 10th month and January the 11th)
March 24, 1750 was followed by March 25, 1751 (March 25 was the first day of the "Old Style" year)
December 31, 1751 was followed by January 1, 1752 (the switch from March 25 to January 1 as the first day of the year)
September 2, 1752 was followed by September 14, 1752 (drop of 11 days to conform to the Gregorian calendar)
So next time you look at a simple calendar, think of the journey it took to create.