In the 11th century, the Muslim holdings fractured into rival Taifa states (Arab, Berber, and Slav), allowing the small Christian states the opportunity to greatly enlarge their territories. The arrival from North Africa of the Islamic ruling sects of the Almoravids and the Almohads restored unity upon the Muslim holdings, with a stricter, less tolerant application of Islam, and saw a revival in Muslim fortunes. This re-united Islamic state experienced more than a century of successes that partially reversed Christian gains.