Álvar Fáñez

The Muslim ruler al-Mu'tamid of Sevilla, following the fall of Toledo to the Christians and Alfonso's subsequent oppression of Muslim vassals, takes a desperate decision and calls for the help of Yusuf ibn Tashufin, the Almoravid emir of North Africa, and his Saharan Berber tribesmen.

The emirs of the smaller taifa kingdoms of Islamic Iberia had found, after Alfonso VI captured Toledo in 1085 and invaded the taifa of Zaragoza, that they cannot resist against his possible conquest without external assistance.

Yusuf ibn Tashfin, Sultan of Morocco and leader of the ascetic Muslim Berbers known as the Almoravids, is invited by them, with some reluctance, to fight against Alfonso VI.

He replies in 1086 to the call of three Andalusian leaders (Al-Mu'tamid ibn Abbad and others) and crosses the straits to Algeciras, disembarking at the end of July.

Yusuf moves to Seville, and from here, accompanied by the emirs of Seville, Granada and the Taifa of Málaga, marches to Badajoz with a large combined army.

Alfonso VI abandons the siege of Zaragoza, recalls his troops from Valencia and appeals to Sancho I of Aragon for help.

Finally he sets out to confront the enemy northeast of Badajoz, where the two armies meet on October 23, 1086 at the Battle of the Sagrajas.

Alfonso reaches the battleground with some twenty-five hundred men, including fifteen hundred cavalry, in which seven hundred and fifty are knights, but finds himself outnumbered, reportedly three to one.

The two leaders exchange messages before the battle.

Yusuf is reputed to have offered three choices to the Castilians: convert to Islam, to pay tribute (jizyah), or battle.

French nobles arrive with reinforcements, but are too late to save the Castilian-Aragonese forces from a crushing defeat.

Many Jews reportedly fought together with Alfonso against the Almoravids.

The Moslem armies also had a large number of Jews serving in them, so much so that the battle had been arranged not to fall on the Sabbath.

While the numbers may be exaggerated, they reflect the fact that Jews actually took part in most of the Spanish wars of the period.

At least half the Castilian army is lost.

One lone source claims that only five hundred knights returned to Castile, although others do not support this low figure, so it seems that most of the nobility survived.

The dead include counts Rodrigo Muñoz and Vela Oveguez.

King Alfonso VI sustains an injury to one leg that will cause him to limp for the rest of his life.

Casualties are also heavy on the Almoravid side, especially for the hosts led by Dawud ibn Aysa, whose camp had been sacked in the first hours of battle, and by the emir of Badajoz, al-Mutawakkil ibn al-Aftas.

The Sevillan emir al-Mu'tamid had been wounded in the first clash but his personal example of valor had rallied the al-Andalus forces in the difficult moments of the initial Castilian charge led by Alvar Fañez.

Those killed include a very popular imam from Cordoba, Abu-l-Abbas Ahmad ibn Rumayla.

The battle is a decisive victory for the Almoravids but their losses mean that it is not possible to follow it up.

Yusuf has to return prematurely to Africa due to the death of his heir.

Castile suffers almost no loss of territory and is able to retain the newly occupied and psychologically important city of Toledo.

However, the Christian advance will be halted for several generations while both sides regroup.

Alfonso appeals for help to the rest of Christendom in the face of the Almoravid threat, and a small expedition is organized as a result; these proto-crusaders’ do not reach Alfonso's lands, instead wasting their energies and resources in an unsuccessful siege of the Muslim outpost of Tudela.

Yusuf ibn Tashfin besieges Aledo but is forced to retreat by the arrival on the scene of the troops of King Alfonso VI.

A string of Christian victories under Rodrigo Diaz de Vivar and successful Christian incursions into Moorish territory compels Tashfin’s return to Spain in June of 1089 at the head of a large army.

Joined in battle by some of the petty Moorish rulers, he battles Alfonso’s forces with no success, and withdraws to North Africa.

The Almoravids are determined to defeat the Kingdom of Castile and roll back the advances of the Reconquista; to that end, Almoravid leader Tamim ibn-Yusuf, leading the forces of Granada, sets out for Jaén in early May.

Here he meets the forces of Córdoba and …

…they continue together to Chinchilla, where they are joined by the forces of Murcia and Valencia under Muhammad ibn Aysa and Abdallah ibn Fatima, their respective governors.

The Muslim forces march on Uclés, which offers no resistance and is captured on May 27.

The Almoravids now spread out, sacking other Christian settlements in the valley of the Tagus, while the inhabitants flee.

The garrison of Uclés meanwhile takes refuge in the alcázar.

The Historia Compostelana says that it was the heir, Sancho, who initiated a counterattack.

This is plausible in light of the fact he had already been granted the rule of Toledo by his father, who is in the north of the kingdom at the time of the Almoravid offensive.

Sancho had probably moved south with a sizable army in April in preparation for a summer of campaigning.

His army included eight Leonese counts and Castilian magnates (los ochos condes of legend), who, with their heavy cavalry retinues, probably count for a fifth of the total heavy cavalry resources of the crown.

Including Sancho’s personal guard, the number of Christian troops is probably about four hundred knights and an equal number of squires and grooms: about twelve hundred men total.

A contingent of townsmen from Calatañazor, Alcalá, and Toledo, led by their alcaldes, numbering probably seven hundred and fifty, mostly infantry but some light cavalry, had joined the main force before the battle.

Including three hundred or so men involved in the baggage train, Bernard Reilly estimates a total number of twenty-three hundred Christian troops, while the Arabic sources mention three thousand Christian heads piled in front of Uclés to terrorize the citizens.

It has been suggested that the Muslims forces would have had to be far superior in numbers in order to execute the successful enveloping tactic they did.