The Roman month Februarius was named after the Latin term februum, which means purification, via the purification ritual Februa held on February 15 (full moon) in the old lunar Roman calendar. January and February were the last two months to be added to the Roman calendar, since the Romans originally considered winter a monthless period. They were added by Numa Pompilius about 713 BC. February remained the last month of the calendar year until the time of the decemvirs (c. 450 BC), when it became the second month. At certain intervals February was truncated to 23 or 24 days; and a 27-day intercalary month, Intercalaris, was inserted immediately after February to realign the year with the seasons.
Under the reforms that instituted the Julian calendar, Intercalaris was abolished, leap years occurred regularly every fourth year, and in leap years February gained a 29th day. Thereafter, it remained the second month of the calendar year, meaning the order that months are displayed (January, February, March,. , December) within a year-at-a-glance calendar. Even during the Middle Ages, when the numbered Anno Domini year began on March 25 or December 25, the second month was February whenever all twelve months were displayed in order.
The Gregorian calendar reforms made slight changes to the system for determining which years were leap years and thus contained a 29-day February.
Julius Caesar, back about 2000 years ago, made a major change in our calendar. He made it pretty much what we have today, except that he was a little off on the leap years, so Pope Gregory, about 1400 years later needed to add a few days to get things back in sync. Back in Julius Caesar s day, the year only had ten months. Julius Caesar decided that he would add two months, one in honor of himself, the other in honor of his father, Augustus Caesar.
These are the months of July and August. He didn t want them to be shorter than any of the other months, so he took two days from February so they could both be 31 days long. Otherwise, the months would alternate 30 days / 31 days. September comes from the Latin word septus, which means seven, and it was originally the seventh month, but became the ninth month after Julius added his two months. Same with October, which meant eight, November, which meant nine, and December which meant ten. We get the word decimal from the Latin word for ten. We get the word octopus, which has eight legs, from the Latin word for eight.