of support and loyalty. Not all the tribes, however, accepted the temporal and even legal role that the imams arrogated to themselves; consequently, many imams (Imam Yahya and Imam Ahmad in the twentieth century included) complained bitterly about the tribes' inordinate political power. See also Alliance of Yemeni Tribes References Almsaodi, Abdulaziz. Modern history of Yemen Bibliography External links Social History of Yemen Arab militant groups Yemeni Revolution Tribes of Arabia Yemeni tribes Rebel groups in Yemen Banu Hamdan Organizations of the Arab Spring Organizations of the Yemeni Crisis (2011–present) Confederations