The Sufyanid line founded by Mu'awiya failed in 683 and Umayyad authority was challenged in the Second Muslim Civil War, but the dynasty ultimately prevailed under Marwan I, who founded the Marwanid line of Umayyad caliphs. The Umayyads drove on the early Muslim conquests, including North Africa, Spain, Central Asia, and Sindh, but the constant warfare exhausted the state's military resources, while Alid revolts and tribal rivalries weakened the regime from within. Finally, in 750 the Abbasid Revolution overthrew Caliph Marwan II and massacred most of the family. One of the survivors, Abd al-Rahman, a grandson of Caliph Hisham ibn Abd al-Malik, escaped to Muslim Iberia (al-Andalus), where he founded the Umayyad Emirate of Córdoba, which Abd al-Rahman III elevated to the status of a caliphate in 929. After a brief golden era, the Caliphate of Córdoba disintegrated into several independent "taifa" kingdoms in 1031, thus marking a definitive end to the Umayyad dynasty.