Career
Promoted to captain on 31 December 1909, Johnson became commanding officer of the cruiser HMS Drake in November 1911, commanding officer of the cruiser HMS Powerful in January 1912 and commanding officer of the cruiser HMS Minerva in December 1912. He went on to be commanding officer of the cruiser HMS Dido in August 1913 and, having been promoted to commodore, became Second in Command of the Dover Patrol in November 1915 during the First World War. In 1915 he received letters on vellum in connection with operations during the sinking of submarine Master of Science U-8.
After the War, Johnson became commanding officer of the battleship HMS Marlborough in October 1918 and was appointed a Companion of the Order of the Bath "for valuable services in command of HMS Marlborough during the operations in Kaffa Bay, Russia" in 1919.
He went on to be Rear Admiral, Reserve Fleet in April 1921 and Admiral Superintendent of Malta Dockyard in February 1924. He was promoted to vice admiral on 1 March 1926 and to full admiral on 8 May 1930.