Alvar Fáñez de Minaya
was the military commander to El Cid
(Rodrigo Diaz de Vivar) during his exile and his conquests as part of the Reconquista
. Minaya was also his nephew through Cid's younger sister and therefore was first cousin to the Cid's daughters.
He was a capable man who was willing to play second-fiddle to Cid. He often was given military command when Cid split his forces (a common occurrence given his style of command).
Fáñez died in mid-April 1114 defending Queen Urraca's rule against rebelling Segovians.