Born in Mecca, Hejaz, Ottoman Empire, Abdullah was the second of four sons of Hussein bin Ali, Sharif of Mecca, and his first wife, Abdiyya bint Abdullah. He was educated in Istanbul and Hejaz. From 1909 to 1914, Abdullah sat in the Ottoman legislature, as deputy for Mecca, but allied with Britain during World War I. Between 1916 and 1918, he played a key role as architect and planner of the Great Arab Revolt against Ottoman rule that was led by his father Sharif Hussein. Abdullah personally led guerrilla raids on garrisons.