The first caliph, Abu Bakr (r. 632–634), belonged to the Banu Taym, as did Talha ibn Ubayd Allah, a prominent companion of Muhammad, a leading member of the community after his death in 632, and one of the wealthiest figures of the early Muslim state.
[1] Umar's grandfather, Ma'mar, was Talha's paternal uncle,[2] and a companion of Muhammad, who converted to Islam with the bulk of the Quraysh after the conquest of Mecca in 630.
[3] Ubayd Allah was a commander in the conquest of the major Sasanian fortress city of Istakhr in Fars and most likely died during the operation, though the sources cite different years (643–644, 649–650, or 650–651).
[2] The Zubayrids' main challenge in Iraq came from the ruler of Kufa, al-Mukhtar al-Thaqafi, who ruled in the name of the son of Caliph Ali (r. 656–661), Muhammad ibn al-Hanafiyya.
The Zubayrid governor of Basra, Mus'ab ibn al-Zubayr, went on the offensive against al-Mukhtar in 686, appointing Umar as the commander of the left wing of his army at the Battle of Harura.
He pursued them to Istakhr, where after a tough battle in which he lost his son, Umar put the Azariqa to flight at the Tamastan bridge near the city.
The uprising ended with the withdrawal of Khalid to Syria and the punishment of the pro-Umayyad tribal soldiers who remained in Basra by Mus'ab's order.
[9] Abd al-Malik defeated Mus'ab in 691 and the Umayyads killed Ibn al-Zubayr in Mecca the following year, bringing most of the Caliphate under their rule.
[4] Abd al-Malik appointed Umar to lead a campaign against Abu Fudayk, the leader of the Kharijite Najdat faction which had taken over eastern Arabia during the civil war.