​​​Between 1923 and 1937, Commander James Campbell Clouston served in numerous capacities both on shore and aboard Royal Navy ships. In May 1937, he became the commanding officer of HMS ISIS, which was based in Malta.

​In 1935, he married Gwyneth Vanderpump. To remain close to one another, she travelled around the Mediterranean in merchant ships, allowing them to spend time together whenever he was on shore. They had their first son in 1938, born in the UK, and would go on to have a second son in 1940.

​In 1940, Commander Clouston continued in command of HMS ISIS, though the ship was in dry dock for repairs following damage sustained in Norway.

​On 1 June 1940, Clouston returned to Dover to review orders for a planned evacuation the following day. On 2 June, he and a naval party boarded two motor launches to return to Dunkirk. They were spotted and attacked by the Luftwaffe. Clouston’s launch was sunk. He waved to the crew of the other launch to get away and avoid the same fate.

​Clouston attempted to swim to another vessel seen some distance away. Unable to reach it, he turned back to the broken remains of his own sunken vessel. He was never seen alive again. His body was eventually recovered, and he is now at rest at the Commonwealth War Graves Commission Becklingen War Cemetery. He is buried in Plot 10, Row J, Grave 2.