Medieval Conquerors and Invaders
The Byzantine Empire managed to repulse the barbarian invasions which destroyed the Western Roman Empire but had to face the Muslim conquests already in the first half of the 7th century. The rise of Islam in the Arabian Peninsula in the 630’s was followed by rapid Arab territorial expansion under Muhammad’s successors, the caliphs who were both religious and political leaders of the Muslim world.
The first to fall in the Muslim hands were the Sassanids, the Byzantine old rivals but the next to fall were the Byzantine territories: Syria, Palestine and Egypt. The Arabs established themselves as an important political and military power in the Mediterranean region by 661 but at the same time broke out serious inner conflicts which resulted in the split of Islam into the Sunni and Shi’a branches. The conflicts were provoked by disagreement over Ali’s (Ali ibn Abu Talib) right to the caliphate and resulted in the outbreak of a civil war known as the First Fitna which ended with Ali’s assassination and establishment of the Umayyads as the first Islamic dynasty.
The Byzantines took advantage of the civil war between the Sunni and Shi’a branches and retook the initiative. By using the so-called Greek fire, a flammable petroleum-based mixture which can not be put out with water, the Byzantines decisively defeated the Arabs in the Battle of Syllaeum in 678, forced them to lift the Siege of Constantinople and to pay tribute to the Byzantine Emperor. The Arab threat to the Byzantine Empire ceased for about three decades when the Umayyads laid siege to the Byzantine capital for the second time. However, the Arabs suffered another defeat and were forced to retreat in 718.
The Arabs continued their expansion in North Africa despite suffering defeat against the Byzantine Empire. Under Umayyads, the Arabs conquered the entire North Africa by the early 8th century, while the Berbers of northern Africa who converted to Islam invaded and conquered the Iberian Peninsula (with exception of the Kingdom of Asturias) between 711 and 718. The Umayyads invaded the Frankish territory several times from the Iberian Peninsula but Muslim conquests in Western Europe came to an end after the Battle of Tours in 732 in which Charles Martel decisively defeated the Muslim forces. However, it took seven centuries for the Christian Kingdoms of the Iberian Peninsula to put an end to the Muslim rule in the Iberian Peninsula.
Muslim defeat in the Second Siege of Constantinople in 718 and in the Battle of Tours in 732 ended the Arab conquests in Europe with exception of conquest of the Byzantine Sicily and parts of Southern Italy by the Aghlabids of Ifriqiya (today’s western Libya, Tunisia and eastern Algeria) in 827. The Muslim rule in Sicily lasted until the Norman conquest in 1061, while the Arab Caliphate under Abbasid Dynasty which has overthrown the Umayyads in 750 began to decline in the early 9th century. Abd ar-Rahman I who escaped the massacre of the Umayyads established himself as an independent Emir in the Iberian Peninsula in 756, while the rise of local dynasties and decline of central authority resulted in fragmentation of the Arab Caliphate into a loose confederation of states under nominal authority of the Abbasid Caliphs.