The sitter was the second son of Sir William Rooke (d. 1691). His naval career is said to have begun when he volunteered during the second Dutch War. In the Battle of Solebay (1672) he was lieutenant of the 'London', flagship of Sir Edward Spragge. By 1691 he had been promoted to the position of Rear-Admiral of the Blue Squadron and he distinguished himself in the Battle of Barfleur in the same year. The following years were less successful but he continued to rise in the naval hierarchy, becoming Commander-in-Chief of the Grand Fleet in 1703. His reputation was, however, fully restored with the capture of Gibraltar in that year.