Igbo calendar

The Igbo calendar (Igbo: Ògụ́àfọ̀ Ị̀gbò^{[citation needed]}) is the traditional calendar system of the Igbo people from present-day Nigeria. The calendar has 13 months in a year (afo), 7 weeks in a month (onwa), and 4 days of Igbo market days (afor, nkwo, eke, and orie) in a week (izu) plus an extra day at the end of the year, in the last month. The name of these months was reported by Onwuejeogwu (1981).[1]

Although worship and spirit honoring was a very big part in the creation and development of the Igbo calendar system, commerce also played a major role in creating the Igbo calendar. This was emphasized in Igbo mythology itself. An example of this is the Igbo market days of which each community has a day assigned to open its markets, this way the Igbo calendar is still in use.

Some Igbo communities have tried to adjust the thirteen month calendar to twelve months, in line with the Gregorian calendar.[2]

The calendar is neither universal nor synchronized, so various groups will be at different stages of the week, or even year. Nonetheless the four-eight day cycle serves to synchronize the inter-village market days, and substantial parts (for example the Kingdom of Nri) do share the same year-start.