Ramiro marched on Graus again in the spring of 1063, but this time the Zaragozans had with them 300 Castilian knights under the infante Sancho the Strong and (possibly) his general Rodrigo Díaz de Vivar, better known as El Cid.
[5] The presence of the Cid at the battle is based on a single source, the generally reliable Historia Roderici, which alleges that he was the alférez of Sancho at the time.
The Fragmentum historicum ex cartulario Alaonis records only that occisus est a mauris in bello apud Gradus (he [Ramiro] was killed by the Moors in war near Graus), with no mention of the Castilians.
[8] Charles Bishko, summarising the position of Pierre Boissonnade, explains how the battle of Graus gave impetus to the War of Barbastro of the next year: .
Graus, in this Hispanic prelude to the Palestinian gesta Dei per Francos, serves as an Iberian Manzikert, with King Sancho Ramírez—like the legates of the Emperor Alexius Comnenus at Piacenza—appealing in desperation for papal and Frankish succor.