The Battle of Cervera took place near Espinosa de Cervera on 29 July 1000 between the Christian troops of counts Sancho García of Castile and García Gómez of Saldaña and the Muslim Caliphate of Córdoba under the hajib Almanzor. The battle, "tremendous and difficult to describe", was a victory for Almanzor. The battle is listed as the fifty-second of Almanzor's career in the Dikr bilad al-Andalus.
Causes and preparations
A truce between Castile and Córdoba had existed since the succession of Sancho García, but in 999 it was broken when the count refused to pay the annual tribute and came to the aid of his Christian neighbour, García Sánchez II of Pamplona, when Almanzor attacked him. On 21 June 1000 an army left Córdoba under Almanzor for a punitive expedition against Castile. The subsequent campaign is the most well-recorded of Almanzor's many wars after his Compostela campaign of 997. The primary historian is Ibn al-Khatib, who derived his Arabic account partially from Ibn Hayyan, himself relying on the eye-witness testimony of his father, Jalaf ibn Husayn ibn Hayyan, one of the combatants on the Muslim side and a secretary to Almanzor. Ibn al-Khatib records that the campaign was the most intense and difficult Almanzor ever waged, that preparations took an especially long time, and that all the rulers of Christian Spain were allied against him, with troops from all the Christian realms assembled together.
Almanzor crossed the Duero and invaded Castile near Madinat Selim, where he sighted an army under Sancho García and the "Galician kings", consisting of troops from as far as Pamplona and Astorga. Almanzor passed by the fortresses of Osma, San Esteban de Gormaz, and Clunia, which had been in Muslim hands for several years at that point. Just north of Clunia he was surprised to find a large Christian army. Sancho, who had been elected leader of the entire army by the assembled troops, was encamped at the rock of Yarbayra (Peña de Cervera), a central location, well situated for supplies, and inaccessible due to its geography. The implication of these events is that Sancho's planning and communications had been superior to those of Almanzor. The roads from Clunia, the northernmost Muslims garrison, led to Tordómar, Lara, and Salas de los Infantes through the narrow pass of the Yecla, which passed through the Peña de Cervera before widening into the basin of the river Arlanza.
Evolution of the battle
The dispersed would have continued not having the means of the protection of God, the ponderous perseverance of Almanzor and the magnificent firmness with which he himself worked, notwithstanding the greatness of his alarm and his private confusion before the development of events. Such a state was reflected in the imploring attitude of his hands, in his death-like moans, and in the vehemence with which he repeated the Koranic ejaculations of the return to God. The luck changed, then, because God helped the Muslims with his [direct] aid and with men who knew how to resist . . .
According to Ibn al-Khatib the Christians solemnly swore an oath not to retreat from battle. Almanzor was aware of his disadvantaged position—the Christians had a stronger camp and better sightlines, with a large open field before them—but his viziers could not agree on how to proceed. Then, without planning and without strategy, the Christian host descended on the unsuspecting Muslims and the battle soon evolved into a general mêlée. Almanzor's right and left columns were attacked simultaneously and soon fell back, which inspired the Christians to press their advantage even more boldly. The majority of the Muslim rear, disoriented by the unorganised attack and disheartened by the result, fled.
According to the eyewitness Jalaf ibn Husayn, Almanzor, with his escort, observed the action from atop a short hill near the field. While he was debating whether to throw his retinue into the fight the right wing broke, which furthered the confusion. One of Almanzor's secretaries, Abd al-Malik ibn Idris al-Yaziri, said to Said Ibn Yusuf, as reported by Ibn al-Qalina, "Come to say goodbye, O martyr, because surely today you must die." By the end of the day Said Ibn Yusuf was dead.