How is Abbas related to Muhammad?

Relation to Muhammad

Al-ʿAbbās, who passed away around 653, was the uncle of the Prophet Muhammad. He belonged to the Hashemite clan of the Quraysh tribe based in Mecca. Starting in approximately 718, members of his lineage endeavored to take control of the empire from the Umayyad dynasty and, through adept propaganda, garnered significant support, particularly from Shiʿi Arabs and Persians.