He attained the highest noble rank (count), like his maternal grandparents, Rodrigo Pérez de Traba (el Velloso) and Fronilde Fernández.
He commanded in the centre, among the forces of Alfonso VIII of Castile, either immediately aft of or flanking the main vanguard under Diego López II de Haro.
[4] In 1220–21, Rodrigo and his noble allies were in rebellion against Berenguela's successor, Ferdinand III; they even offered the throne to Blanche's son, the future Louis IX.
[5] Rodrigo had mortgaged some properties to the king in exchange for money to finance a Crusade to the Holy Land.
In December 1221, though they were subjects of the Castilian crown, Rodrigo and Alvar did homage to Sancho VII of Navarre for the castle of Los Fayos on the Moncayo.