During the Rashidun caliphate (632–661), control of the Arabian Peninsula and crushing defeat of the Sasanid Empire was achieved within a decade. The Rashiduns then confronted the Byzantine Empire, in Syria and Egypt. The Arab conquest of North Africa was staccato, with two sweeping invasions subsequently halted by military reverses and internal strife. The Umayyad caliphate would launch a third decisive invasion, completing conquest of North Africa in 709. To their north, the Rashidun quickly drove the Byzantines from Syria. Their new Syrian governor, Muawiya (the future first Umayyad caliph), commissioned the first Muslim navy, enabling three (unsuccessful) sieges of Constantinople and the progressive capture of Mediterranean islands – Cyprus, Crete, Sicily, the Balearics. With North Africa secured, the invasion of Europe was launched through Spain. In central Spain, the defeat of the Visigoth army opened the way to conquest of the Iberian Peninsula.