Career
He fought in the southern front during the First Carlist War on the side of the Liberals (Christinos), and made himself famous for marching at the head of his lancers and riding at the spot where the enemy was most numerous. At Arcos de la Frontera, in charge of a squadron of 70 horsemen, he managed to detain a Carlist column until Liberal reinforcements arrived. He was awarded the Cross of Saint Ferdinand as a result (Cruz Laureada de San Fernando).
On the northern front, he fought at the Battle of Mendigorría and later captured Belascoáin from the Carlists in 1838, thereby earning his noble title.
In 1840, he was named Captain-General of New Castile. Later, in 1841, he joined O"Donnell"s revolt against Baldomero Espartero.
Diego de León was arrested and later executed by firing squad.