October is commonly associated with the season of autumn in the Northern hemisphere and spring in the Southern hemisphere, where it is the seasonal equivalent to April in the Northern hemisphere and vice versa.

The eighth month in the old Roman calendar, October retained its name (from the Latin octō meaning “eight”) after January and February were inserted into the calendar that had originally been created by the Romans. In Ancient Rome, one of three Mundus patet would take place on October 5, Meditrinalia October 11, Augustalia on October 12, October Horse on October 15, and Armilustrium on October 19.