The deposed Muhammad III, assassinated in Uclés when he is fifty years old, is believed to have died by poison..

His only child is the famous poet Wallada bint al-Mustakfi, whose early childhood was during the high period of the Caliphate of Córdoba, under the rule of Al-Mansur Ibn Abi Aamir.

Her adolescent years had come during the tumultuous period following the eventual succession of Aamir's son, Sanchuelo, who in his attempts to seize power from Hisham II, had plunged the caliphate into civil war.

As Muhammad III has no male heir, Wallada inherits his properties.

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.

The Christians arrive near Uclés and set up camp on May 28.

Tamim assembles his force with the Córdobans under Muhammad ibn Abi Ranq in front, his own Granadans behind them; the Valencians and Murcians make up the flanks.

Battle is joined the next day with a Christian cavalry charge.

Though initially successful against the Córdobans, the charging Christians are quickly surrounded while engaging the Granadans and the main force retreats to their camp.

The Murcians and Valencians meanwhile attack the baggage.

The infantry is dispersed; the cavalry is caught in their own camp and slaughtered.

Sancho, his horse killed and with a small force of seven of his own men, escapes and flees towards Belinchón, but is killed by his Muslim subjects, who take advantage of the battle to revolt.

The only count to escape is Álvar Fáñez, who leads a large body of horse north to organize the defense of the upper Tagus.

In the aftermath, the Muslims lure the garrison of the Uclés into sallying from the alcázar and defeat them.

The Almoravids follow up their success by taking the castles of Huete and Ocaña, and a few small others.

The identity of the seven dead counts must be patched together from various sources.

Crónica Najerense records the death of García Ordóñez, the count of Nájera.

Lucas de Tuy records his death also, as well as that of the heir and of Martín Laíñez.

Probably Martín's son, Gómez Martínez, also perished.

Based on their sudden disappearance from contemporary documents, Reilly suggests that Fernando Díaz, the greatest magnate of Asturias, and the Castilian magnates Diego and Lop Sánchez, probably brothers but not technically counts, were killed in the battle.

García Álvarez, the king's alférez, may have perished, but he was never a count and his disappearance from the record may be due only to his replacement.

An attempt by the Spanish Army of the Center to recapture Madrid ends with the complete destruction of the Spanish forces at Uclés on January 13 by Victor's I Corps.

The French lose two hundred men while their Spanish opponents lost six thousand eight hundred and seventy-seven.

King Joseph makes a triumphant entry into Madrid after the battle.