Leonese noble from the 11th century, purely legendary character who appears in Chronicles and contemporary and subsequent songs (see the singing of Sancho II) as the lover of Urraca Fernández, daughter of Fernando I of Castile.
According to the legend, October 6, 1072, while Sancho II was besieging the city of Zamora, who defended his sister Urraca, Bellido left the city by pretending he/she had disagreements with the Governor of this square, Arias González, and asked the besiegers that they accept it in their ranks. He/She promised Sancho teach most vulnerable points of the Zamora wall, which both came out of night in direction to it. At the foot of the wall and protected by darkness, Bellido slew the monarch with his spear and went on the run. The Knights of Sancho, among which the Cid, was left in his pursuit.
At this point the different legends differ, on the one hand some writings maintain that one of the city gates opened and the regicide took refuge in it, thus escaping their pursuers. Other sources, close to the figure of the Cid, ensure that the zamoranos closed the wall to him and that, forced to flee to open field, was hit by the Cid and wronged. Third versions affirm that the Cid, in Chase, did not give scope and which could only hurt him slightly.
Data that confirm the existence of this character, not found so far its veracity takes refuge in the legend. Bellido has personified throughout history, and mainly in medieval songs, the prototype of the traitor and the regicide.