Aleppo (Moslem Invasion of Syria).
This place was besieged by the Moslems under Abu Obeidah and Khaled in 638, and the city almost immediately surrendered, but the garrison retired to the citadel, where under Youkinna it maintained a stubborn defence for five months, and caused heavy loss to the besiegers. At last the citadel was taken by surprise, and Youkinna became a convert to Mohammedanism. This was the last serious resistance offered in Syria to the invading Moslems.