In the 1080s, several Muslim taifa kingdoms in al-Andalus asked the Almoravid leader Yusuf ibn Tashfin for military help against expanding Christian powers, especially after the fall of Toledo (1085). This invitation opened the door for a North African power to shape the later stages of the Reconquista, first as an ally and soon as a ruler.
Yusuf ibn Tashfin’s army, reinforced by Andalusi allies, defeated King Alfonso VI at the Battle of Sagrajas (also called az-Zallaqah). The victory checked rapid Christian expansion and raised Almoravid prestige in Iberia, making later Almoravid political control more possible.
The Almoravids returned to Iberia and joined Andalusi forces to besiege Aledo, a strategic Christian-held fortress. The siege failed, revealing how hard it was to coordinate the taifa rulers and showing Yusuf that military aid alone would not stabilize al-Andalus.
Starting in 1090, Yusuf ibn Tashfin moved from intervention to direct rule, deposing several taifa rulers. This shift replaced fragmented taifa politics with Almoravid governance and a stricter Maliki legal approach, changing the political landscape the Christian kingdoms faced.
After pressure from Almoravid forces, Seville—one of the most powerful taifa capitals—fell under Almoravid control in 1091, and its ruler al-Muʿtamid was removed and later died in exile in North Africa. The fall of Seville symbolized how quickly Almoravid “help” had become imperial takeover.
In 1094 Rodrigo Díaz de Vivar (“El Cid”) seized Valencia, showing how fluid the period was: Christian and Muslim leaders sometimes fought as rivals or allies based on local advantage. The city became a key eastern prize that the Almoravids later treated as essential to unify their Iberian holdings.
In 1094 the Almoravids captured Lisbon from a Castilian-backed governor and also crushed resistance in the west, including the Badajoz taifa’s last ruler. These gains strengthened Almoravid control over the western frontier and tightened pressure on emerging Portuguese and Leonese-Castilian positions.
After El Cid’s death, Valencia was defended by his widow Jimena Díaz but became hard to supply and hold. The Almoravids besieged the city and reoccupied it in 1102, reestablishing Muslim control on the eastern coast and reducing a major Christian foothold south of Aragón.
The Almoravids defeated a major León-Castilian force at the Battle of Uclés, killing many leading nobles and Alfonso VI’s heir. The victory damaged Christian leadership and morale, but it also showed a recurring limit of Almoravid success: they could win battles yet still struggle to capture strongly held centers like Toledo.
In 1110 the Almoravids absorbed the Taifa of Zaragoza, turning a former taifa capital into a key base in the Upper March (the northeastern frontier). Control of Zaragoza strengthened Almoravid reach against Aragón and Catalan counties, but it also made the city a major target for Christian siege warfare.
After a major siege campaign, Alfonso I of Aragón took Zaragoza in December 1118. The loss reduced Almoravid power in the Ebro valley and marked a turning point where Christian kingdoms began gaining momentum against a now overstretched Almoravid state.
From the 1120s, the Almohad movement, launched by the preacher Ibn Tumart, grew into a serious political and military challenge in North Africa. As resources were pulled toward fighting this new threat, Almoravid leaders found it harder to defend al-Andalus against continuing Christian pressure.
In 1139 Portuguese forces under Afonso Henriques defeated an Almoravid-led army at Ourique, part of a wider struggle over the western frontier. The battle became linked to Portugal’s growing independence and showed that Almoravid control in Iberia was being challenged from multiple directions.
In 1147 the Almohads conquered Marrakesh after a siege, taking the Almoravid capital and killing the last Almoravid ruler there. This collapse in North Africa effectively ended Almoravid authority and accelerated the transition in Iberia toward Almohad influence and the “second taifa” period in some areas.
Almoravid campaigns and rule in Iberia (1086–1147)