When Ponsonby's command, the 5th Dragoon Guards, arrived in the Peninsula in October 1811, it became part of John Le Marchant's heavy cavalry brigade. For the rest of the war, this brigade included the 5th Dragoon Guards and the 3rd and 4th Dragoons. Ponsonby took part in Le Marchant's famous charge at the Battle of Salamanca in July 1812. On that occasion, the British heavy dragoons rode down one French infantry division and part of a second before being repulsed. Upon Le Marchant's death in the battle, Ponsonby took over the brigade, participating in the campaign that included the Siege of Burgos. In 1813, Ponsonby led his 1,200-strong cavalry brigade at the Battle of Vitoria. During the Battle of the Pyrenees and the autumn campaigns in the mountains, the Duke of Wellington sent the bulk of his cavalry to the rear. On 25 January 1814, Ponsonby took leave of his brigade and in the final battles in France, Lord Charles Manners exercised command.