トゥール・ポワティエ間の戦い
According to Majid Khadduri, the fundamental distinction between "Dar al-Islam" and "Dar al-Harb" was introduced after the defeat of the Umayyad Caliphate at the Battle of Tours in 732 which prevented the expansion of Islam to the north, while at the same time the expansion of the caliphate to the east had been halted.