He became a major in the quartermaster's department in 1806 and in 1812, he was appointed assistant quartermaster general serving in Spain and Portugal during the Napoleonic Wars. For his services as assistant quartermaster general at the battles of Vitoria, the Pyrenees, Nivelle, Orthez and Toulouse he received a gold cross and one clasp. Dickson was also at the Battle of Waterloo and the capture of Paris. He was created a Knight Commander of the Order of the Bath in 1815. On 15March 1818 he married Jemima, the youngest daughter of Thomas Brooke of Mere Hall in Cheshire. He continued as assistant quartermaster general in England and Ireland after the wars and was promoted colonel 27May 1825.