Maybe your cultures rely heavily on holidays and festivals. Maybe the Zodiac signs in your world play a major role in your magic system. Whatever is your reason for creating a calendar, here you can find the basics of how to do it!
When it comes to calendars, there are three main types: lunar, solar and lunisolar. Each of these types tracks time differently.
Lunar calendars, as the name suggests, are based around the Moon, more specifically its phases. Each month in a lunar calendar is correspondent to a full lunation (moon cycle), which is approximately 29.5 days. This means that often, months in a lunar calendars alternate between 29 and 30 days. However, since this adds up only to 354 days, and lunar calendars don’t usually have any intercalation, the calendar gets out of sync with a solar calendar pretty quickly (11 days per year).
These calendars base their years around the time it takes the Earth to orbit the Sun. This is the system of the Gregorian calendar, which most of us use on an every-day basis. The solar calendar’s months do not correspond to the actual moon phases.
The time in a solar calendar is measured using the position of the Sun on the sky, relative to the stars we see from Earth.
Lunisolar calendars, as you surely guessed, try to combine the best parts of lunar and solar calendars. The dates indicate the time in the tropical year (orbit around the Sun), and the moon phase. An example of this could be the Chinese calendar.
When creating a calendar for your world, you usually have to think about the names of the months. Months can be named after a variety of things, such as gods (June is named after Juno), important events, things that grow in that month, things that happen in that month (for example, the month of March in Czech – Březen – is named after the fact that female animals are pregnant – březí), constellations, names of Moons, important people in history (July is named after Julius Caesar), the order (October was the 8th month). I’m sure you can find more inspiration.
Different cultures and different languages will, of course, have different names for the months.
These were only the basics of creating a calendar. You don’t have to abide at all to the general types I listed here. You could make a calendar based on islands and the time it takes to travel between them. Your cultures don’t have to have names for your months. You should make your world as original as possible while keeping a realistic approach. Too weird, and it may be unbelievable.
Tell me about your calendars in the comments!