How Did The Calendar Come About. About 3000 bce, one of the oldest calendars ever discovered was developed in ancient egypt by the nile river ’s yearly floods. The calendar as we know it today, is named after pope gregory xiii, who introduced it in october 1582.

At the founding of rome around 753 b.c., the original calendar (said to be of romulus himself) looked like this: Our modern calendar began with the julian calendar, introduced by the roman empire in 46 bc under julius caesar.