In the Battle of Campo Maior, or Campo Mayor (an older spelling most often used in English language accounts), on 25 March 1811, Brigadier General Robert Ballard Long with a force of Anglo-Portuguese cavalry, the advance-guard of the army commanded by William Beresford, clashed with a French force commanded by General of Division Marie Victor de Fay, marquis de Latour-Maubourg. Initially successful, some of the Allied horsemen indulged in a reckless pursuit of the French. An erroneous report was given that they had been captured wholesale. In consequence, Beresford halted his forces and the French were able to escape and recover a convoy of artillery pieces.