Islamic Studies
Caliphate & Rulers: From the Rightly Guided Caliphs to the Ottoman Caliphate
In which year AH was the Hijri Calendar introduced?
Explanation
The Hijri Calendar was introduced in 17 AH during Umar's caliphate, on the advice of Ali (RA), with Muharram as the first month.
Reference: Islamic Studies - Caliphate & Rulers
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