Battle of Xiangyang
His grandfather Alagh was the viceroy in Khorazm province under the Mongol Empire. Bayan's father died during the Mongol siege of the stronghold of the Assassins ("Hashshashin"). While Bayan served in Persia with Hulegu's army, Kublai Khan recalled him. Kublai liked him, but he did not hold commanding rank in the Yuan army. After the success of the Battle of Xiangyang in 1273, Kublai appointed Bayan as the commander of the Yuan army and general Aju agreed the decision. Bayan married the niece of Kublai's Khatun Chabi of the Kunggirat. Bayan of the Baarin is wrongly said to had an Iranian or Persian wife but the biography Xiao wrote on Bayano f Baarin does not mention the ethnicity of the wife and says that it was a wife "in Persia".