Major John Henry Dickson was appointed an Ensign in the 51st Regiment in late 1839 and attained the rank of Lieutenant in May 1842. Subsequently employed in the Pegu operations of 1852-53, he was present at the action of Donabew and afterwards attached to four Companies under Captain Irby, until shortly before the capture of Myattoon's stronghold, when he was transferred to the command of a detachment to protect the sick and wounded. Dickson was advanced to Captain towards the end of these operations and to Major in September 1857.