 After Mu'izz's return to Ghur, he, along with Baha al-Din prepared a new Ghurid expedition into Khwarezm.During the same period, a Ghurid prince named Ala al-Din Atsiz married a daughter of Baha al-Din.However, Mu'izz al-Din was soon assassinated in 1206, which resulted in a civil war; Baha al-Din Sam was supported by the native Iranian soldiers, while the Turkic "ghulams" supported Ghiyath al-Din Muhammad's son Ghiyath al-Din Mahmud.