His father was
Joseph O'Donnell O'Donnell and his mother was María Ana de Anhetan. Joseph O'Donnell D'Anhetan was the brother of two other generals who also fought during the
Peninsular War,
Henry O'Donnell, 1st Count of la Bisbal and
Carlos O'Donnell as did his three other brothers, Leopoldo and Francisco, both of whom were killed during the war, and Alejandro.
Early career His father having enlisted him as a child cadet in the
Irlanda Regiment in 1777, he was forced to abandoned his studies at the Royal Military and Mathematics Academy of Barcelona when his regiment, garrisoned at Ceuta, came
under siege in 1790. to
Pedro Caro, 3rd Marquis of la Romana during the
escape of the Northern Division from Denmark. Promoted to colonel at the end of that year, O'Donnell was given command of the Princesa Regiment, remaining with La Romana throughout the May 1809 campaign in Asturias. In 1809, O'Donnell led the 698-strong Cavalry Brigade, made up of four squadrons of the Olivenza Regiment and one squadron of the Santiago Regiment of General
Blake's Army of Aragon at the
Battle of María. He was beaten by
Nicolas Godinot at
Zújar in 1811. After the loss of
Valencia in January 1812, he ably reorganized the fragments of the Spanish army. While
Captain General of
Murcia, he suffered a severe defeat at the hands of
Jean Isidore Harispe at
Castalla in July 1812, a defeat that led to his brother
Enrique O'Donnell having to resign from the Regency Council at Cádiz and he, himself, requesting an inquiry into the defeat. In the meantime, the following month he was commissioned to organise the Reserve Army and was finally fully exonerated of any fault for the defeat at Castalla.
Post-war career He was promoted to lieutenant general in 1815. ==References==