Following Oxford, he entered the Foreign Service and, owing to the national importance of his work at the cipher desk, he was excluded from military service until 1917, when he joined the Grenadier Guards.
Following Oxford, he entered the Foreign Service and in October 1913, at the third attempt. Matthew 2004, p240 Owing to the national importance of his work at the cipher desk, he was exempted from military service until June 1917, when he joined the Grenadier Guards.