 At the time of the Arab conquest, Bilad al-Sham was inhabited mainly by local Aramaic-speaking Christians, Ghassanid and Nabatean Arabs, as well as Greeks, and by non-Christian minorities of Jews, Samaritans, and Itureans.The population of the region did not become predominantly Muslim and Arab in identity until nearly a millennium after the conquest.The Muslim Arab army attacked Jerusalem, held by the Byzantines, in November, 636.