The Diary of a U-boat Commander (The World At War)

William Stephen Richard King-Hall, Baron King-Hall of Headley (21 January 1893 – 2 June 1966) was a British naval officer, writer, politician and playwright. He gained the rank of Commander in the service of the Royal Navy in 1928, before resigning in 1929. He wrote several plays between 1924 and 1940. He joined the Royal Institute of International Affairs in 1929, having previously been awarded their Gold Medal for his 1920 thesis on submarine warfare. (Excerpt from Wikipedia)