Around the time Muhammad was becoming master of Mecca, he sent a letter† to Heraclius, the Christian emperor of the Eastern Roman Empire who had that same year just defeated the Persian Empire after decades of warring. The heart of the prophet’s letter consisted of two Arabic words, aslam taslam—that is, “submit [to Islam] and have peace.”24 It was rejected. Muhammad responded in 629 by sending an expeditionary force of some three thousand Arabs chanting “victory or martyrdom!” into Christian territory.
