This is because in the original Roman calendar, winter did not have months.
November was the ninth month of the ancient Roman calendar.
September was the seventh month in the ancient Roman calendar, as its name indicates.
For its current state, see Roman Catholic calendar of saints.
The ancient Roman religious calendars assign only one day to the festival.
In the earliest Roman calendar, March was the first month, and the god would have been born with the new year.
Initially, however, her feast day was not included in the Roman Calendar.
The feast also continued as a memorial in the Roman Calendar of 1969.
The ordinary year in the previous Roman calendar consisted of 12 months, for a total of 355 days.
On the oldest Roman calendar that had begun with March, it was the third month.