 Months later , on 20 January 1818 , Marques de Sousa was enlisted into the army as a cadet in the 1st Regiment of Light Cavalry in the Division of Royal Volunteers . The regiment had been deployed to Montevideo , the largest town in the Banda Oriental . He fought in the Battle of Pando on 30 March and in the Battle of Manga near Montevideo on 1 April . Successful in both battles , on 24 June he was promoted to alferes ( equivalent to a modern @-@ day second lieutenant ) and named adjutant to the commander @-@ in @-@ chief , Lieutenant General Carlos Frederico Lecor ( then Baron and later Viscount of Laguna ) . 
