Battle of Siffin
Umm Bashir was Hasan's second wife. She was the daughter of Abu Mas'ud 'Uqba b. Amr, who was among those who apposed Kufan's revolt against Uthman. According to Madelung, Ali was hoping to draw him to his side by this marriage. Afterwards Ali appointed him as the governor of Kufa, during the time when himself was involved in the Battle of Siffin. Hasan had two or three children from Umm Bashir. His eldest son, Zayd, his daughter Umm al-Husayn, and probably another daughter named Umm al-Hasan.