Question

Who started Hijri calendar?

Answer 1

The Hijri era is calculated according to the Islamic lunar calendar and not the Julian or Gregorian solar one. It thus does not begin on January 1, 1 CE, but on the first day of the month of Muharram which occurred in 622 CE. Its Julian equivalent was April 19 but it is sometimes mistakenly placed on July 16.

Answer 2

The Islamic calendar employs the Hijri era whose epoch was retrospectively established as the Islamic New Year of AD 622. During that year, Muhammad and his followers migrated from Mecca to Yathrib (now Medina) and established the first Muslim community (ummah), an event commemorated as the Hijr*a.