The Battle of Calatañazor was a legendary battle of the Reconquista that supposedly took place in July 1002 in Calatañazor, in the Province of Soria, between an army of invading Moors under Almanzor and a force of Christian allies led by Alfonso V of León, Sancho III of Navarre, and Sancho García of Castile. Almanzor, who historically died the night of 10–11 August, is said to have died of wounds received in the battle. The battle has been branded as unreal since the 18th century because of the non-existence of any evidence in the chronicles of the time. Its ahistoricity was first demonstrated by Reinhart Dozy in 1881. The French Arabist Évariste Lévi-Provençal attributed the destruction of San Millán de la Cogolla by the Saracens to the campaign in Calatañazor.
Legend
Almanzor was finishing a campaign in Galicia when he decided to invade Castile. He assembled a large army at Calatañazor, where the Leonese and Castilians met him. Thousands of Muslims were slain and Almanzor himself escaped only because of nightfall:
Under cover of darkness he fled with his retinue. The next day, Vermudo marched on the Muslim camp at dawn but found it abandoned and collected instead an enormous booty. García Fernández, having pursued the fleeing Muslims, came away with a large number of prisoners.
The same day as the battle in another part of Spain, a fisherman was seen exclaiming, first in Arabic then in Spanish, "In Calatañazor Almanzor lost the drum". Many Muslims came from Córdoba to see the fisherman, but every time they approached him, he disappeared before their eyes, only to reappear elsewhere repeating the same lament. Lucas of Tuy believed it was the devil lamenting the disaster of Calatañazor (el diablo que llorava la cayda de los moros). Almanzor never ate or drank after his defeat, and dying in Medinaceli, he was buried there.