First World War records on tens of thousands of servicemen and women, released yesterday by the Public Record Office at Kew in London, revealed how Mr Coward was called up at 18 in April 1918 but left without seeing any action.
Mr Coward reported sick within weeks of joining the 28th London Regiment, known as the "Artists' Rifles", and was transferred to hospital where an army doctor said he was "pale, shaky and nervy. Cannot stand any noises".
According to his discharge notes, Mr Coward had suffered headaches and nervous disability since the age of nine when he was knocked down by a bicycle. Medical officers concluded he was "no longer physically fit for war service".
Coward's condition, diagnosed as a neurasthenia (anxiety and listlessness), spared him from war to enjoy a 50-year theatrical career playing the quintessential Englishman.
He became a living legend, writing plays, songs and films, including the inspiring Second World War epic In Which We Serve, in which he played a tough naval officer.
He also wrote or directed several other stirringly patriotic World War Two films.
The previously confidential records released on the 80th anniversary of the end of the First World War also reveal that the British painter, Stanley Spencer, got bronchitis and malaria during a posting in the eastern Mediterranean while in the Royal Berkshire Regiment.
Work starts this week on photographing the records stored in 33,000 boxes, which will be put on microfilm for the public to access.Reuse content