Muslim Iberia became part of the Umayyad Caliphate and would be known as Al-Andalus. The Berbers of Al Andalus revolted as early as 740 AD, halting Arab expansion across the Pyrenee Mountains into France. Upon the collapse of the Umayyad in Damascus, Spain was seized by Yusuf al Fihri. The exiled Umayyad Prince Abd al-Rahman I next seized power, establishing himself as Emir of Cordoba. Abd al Rahman III, his grandson, proclaimed a Caliphate in 929, marking the beginning of the Golden Age of Al Andalus. This policy was the effective power of the peninsula and Western North Africa; it competed with the Shiite rulers of Tunis and frequently raided the small Christian kingdoms in the North.