The Arabs of Syria were people of no consequence until the migration of the powerful Ghassanid tribe from Yemen to Syria, who converted to Christianity and thereafter ruled a semi-autonomous state with their own king under Roman vassalage. The Ghassanid Dynasty became one of the honoured princely dynasties of the Empire, with the Ghassanid king ruling over the Arabs in Jordan and Southern Syria from his capital at Bosra. The last of the Ghassanid kings, who ruled at the time of the Muslim invasion, was Jabla bin Al Aiham.