Probably because most calendars started as lunar or lunar-based. There is also the case that separating the year by month could be beneficial for farmers back

Probably because most calendars started as lunar or lunar-based. There is also the case that separating the year by month could be beneficial for farmers back in the day to plan different activities throughout the year. I've always like the names of the months in the French Republican Calendar[1] because of that. [1]: https://en.wikipedia.org/wiki/French_Republican_calendar#Months https://en.wikipedia.org/wiki/French_Republican_calendar#Mon...