Uthman

   Caliph (q.v.) from 644-656; he succeeded Umar (q.v.). Under him, the Arabs (q.v.) completed much of their westward march across North Africa (q.v.), defeating the Byzantine exarch Gregory (qq.v.) in 647. In the east Mediterranean (q.v.) equally important Byzantine reverses occurred, the first in 648 when, for the first time, an Arab fleet invaded Cyprus (q.v.). In 655, off the coast of Lycia (q.v.), in the first major naval battle with the Arabs, Constans II (q.v.) lost his fleet and almost his life. Further expansion was stalled for several years by the civil war that broke out upon Uthman's assassination in 656.