[5] Stephenson managed to make a favourable impression on Admiral Sir Jackie Fisher, the then Commander-in-Chief, Mediterranean.
[1][6] At the outbreak of the First World War in August 1914, Stephenson was based in the Admiralty, attached to the Naval Intelligence Division.
[2] He was involved in operations in the Dardanelles, and then commanded a fleet of naval trawlers undertaking patrols from Crete.
[1] He went on to command the gunboat HMS Hussar and,[2] (as an acting captain) the Otranto Barrage, a fleet of small boats which attempted to control the exit from the Adriatic Sea, particularly trying to prevent submarines of the Austro-Hungarian Navy breaking out into the Mediterranean.
[1] He was Mentioned in Despatches in December 1918,[7] appointed a Companion of the Order of St Michael and St George in the 1919 New Year Honours,[8] awarded the Greek decoration of Commander of the Order of the Redeemer for his service in the Mediterranean and Adriatic,[9] and was also awarded the United States Navy Distinguished Service Medal.
In 1929, he was part of the official British delegation at the funeral of Marshal Ferdinand Foch, acting as Naval Aide-de-camp to Prince George,[11] and later that year was placed on the retired list, with promotion to rear admiral.
A frequently recounted anecdote is that when inspecting a corvette and its crew, Stephenson suddenly threw his hat on the deck and called it an unexploded bomb.
Although he was disliked by the trainees, who called him "The Terror of Tobermory" and "The Monkey", Stephenson was credited in producing capable sailors who were able to meet the demands of the Battle of the Atlantic.
[1] A noted fictionalised depiction of Stephenson and his Second World War assignment is presented in Nicholas Monsarrat's novel The Cruel Sea.
[13] Over the four-and-a-half years Stephenson ran the school, 911 ships went through 1132 training courses at HMS Western Isles.
He was appointed Honorary Commodore of the Sea Cadet Corps in 1949, a post he held until the age of eighty in 1958, when he finally felt it necessary to step down.