Parker took command of the fifth-rate HMS "Iphigenia" also on the North American Station in March 1818 and then the first-rate HMS "St Vincent", flagship of the Commander-in-Chief, Portsmouth, in May 1830. Having been appointed an extra aide-de-camp to the King on 5 September 1831, he took command of the first-rate HMS "Victory" also at Portsmouth in December 1831 and then the second-rate HMS "Rodney" in the Mediterranean Fleet in August 1835. He was appointed a Companion of the Order of the Bath on 18 April 1839.