Charles entered the war in France on 21st May 1915. From 17th July 1915 the unit was at Ypres. The town was used extensively as a billeting place, and the Ramparts, Prison, and Cloth Hall were always full. The book ‘With the Forty Fourths’ states: “Whenever a shell had found its mark, a call was made on the other units near to help in the rescue work. In 1921 the Press announced that, following upon excavations at the Cloth Hall, the bodies of about thirty infantry were found, and various correspondents asserted that they were present at the original catastrophe on rescue work. No mention was made of R.A.M.C. casualties; but it was while trying to rescue, on 12th August, the very men whose bodies were found in 1921, that some of the 44th got hit. McCallum and Vine were brought back to Pop. and buried, but poor Alf Williams was never found: only his arm with the brassard still on.” Charles was the son of Charles McCallum; and the husband of Christina McCallum of 30 Montrose Street, Lochore, Fife.