Born in Auch in a modest family, Jean-Louis-Brigitte Espagne enlisted in 1787 as a soldier in the Dragons de la Reine (Queen's Dragoons) regiment and then saw a very slow promotion through the ranks.

In 1792, Espagne was maréchal-des-logis (roughly equivalent to sergeant) but the outbreak of the French Revolutionary Wars that year offered numerous opportunities for promotion.

With the outbreak of the War of the Third Coalition, he was promptly sent to serve in Italy, in command of a chasseurs à cheval light cavalry division, combating at the battle of San Michele, on 29 October.

The next year, Espagne was created a Count of the Empire and in 1809 he was called to the command of a cuirassier division in the Army of Germany during the War of the Fifth Coalition.

During the desperate battle of Aspern-Essling, Espagne led his cuirassiers in a series of heroic charges, but was wounded in action during the first day of fighting.