When the Persian shah Ismail I had founded the Safavid empire and forced his subjects to convert to Shiism in the fifteenth century, the decision had been mostly tactical. The shah belonged to a small messianic Sufi Shia order, which had started out as Sunni. As he conquered Ottoman territory and solidified his empire, the Safavid ruler sought to rally his subjects around a distinct identity, sharpening the front line with the enemy.
