The
British Expeditionary Force (BEF) was engaging the Imperial German Army during the
Battle of Mons. During this engagement 14,000 British soldiers were killed, wounded or missing. One of those made POW was Campbell. On 24 August 1914, while commanding the 1 Battalion of
East Surrey Regiment Campbell was taken prisoner. The war diary of the 1st Battalion recorded that on 23 August 1914 that it was a misty and wet day. During fighting on the 24 August five officers and 134 soldiers were lost including Campbell. He spent two years in captivity, at a POW camp in
Magdeburg, central Germany, when he got word from his sister that his mother, Louisa, was dying. He wrote to the
German Kaiser pleading that he be allowed to visit his dying mother. His petition was successful and arrangements were made through the embassy of the
United States of America, which was neutral at the time. Campbell was made to swear that he return to the POW camp after seeing his mother.
Richard van Emden, writing in his 2013 book
Meeting the Enemy, speculated that Campbell would have felt it honourable to return and "he would have thought 'if I don't go back no other officer will ever be released on this basis. He crossed into neutral Holland from Germany and took a ferry to the UK. He later returned to Germany by the same route. Later during his sojourn as a POW, Campbell and other prisoners spent nine months digging a tunnel to escape from their camp and attempted to reach the Dutch border. He was captured near the border and sent back into captivity. After the war, Campbell returned to Britain; he served in the military until 1925. ==Death==