In 1514 Selim I attacked Ismail's kingdom to stop the spread of Shiism into Ottoman dominions. Selim and Ismā'il had exchanged a series of belligerent letters prior to the attack. Selim I defeated Ismā'il at the Battle of Chaldiran in 1514. Ismā'il's army was more mobile and his soldiers better prepared, but the Ottomans prevailed due in large part to their efficient modern army, possession of artillery, black powder and muskets. Ismā'il was wounded and almost captured in battle, and Selim I entered the Iranian capital of Tabriz in triumph on 5 September,