Dalrymple entered the army as an ensign in 1763 at the age of thirteen, and rose rapidly through the ranks becoming Colonel of the Grenadier Guards in 1790, Major General in 1794 and Lt. Governor of Guernsey in 1796 until 1803. The artist first apprenticed to his father, a tailor. Jackson disliked this work and through the kindness of Sir George Beaumont, was given the opportunity to study at the Royal Academy. Jackson first exhibited there in 1804 and exhibited no less than 145 pictures between that year and 1830. It is though his best portrait was that of Flaxman, painted for Lord Dover. At the Academy dinner in 1827, Sir Thomas Lawrence characterized this painting as 'a picture which Van Dyck might have felt proud to own himself the author.