The 10th-century Kilabi invasion may have been encouraged or directly supported by the Qarmatian movement based in eastern Arabia. The Qarmatians, whose troops largely consisted of Bedouin tribes, launched a series of invasions against Syria in the 10th century, the first occurring in 902. The Kilab and other branches of the Banu 'Amir provided the bulk of the Qarmatians' military personnel. At the time, the Arab tribes of Syria and Mesopotamia experienced marked population growth, which coincided with rising grain prices. This, according to historian Thierry Bianquis, made the tribes susceptible to Qarmatian [sic] propaganda denouncing the wealth of the urban Sunni population and the luxury of the pilgrimage caravans. The tribes frequently raided the agricultural lands of Hama, Maarrat al-Nu'man and Salamiyah, but nonetheless integrated well with the rural population due to their shared Shia Muslim faith; the Qarmatians too were Shia, following a version of Ismailism.