[3] Having served in South Africa before the First World War, which began in 1914, Beauman's battalion was amongst the first units of the British Expeditionary Force (BEF) which went to France in August 1914: they were known as the "Old Contemptibles".
After being invalided home in November 1914, he returned to the front in January 1915 when he served as Staff Captain, Deputy Assistant Adjutant and Quarter Master General, and then acting lieutenant colonel of the 1st Battalion of the South Staffordshires.
In May 1918, after receiving a temporary promotion to the rank of brigadier-general, aged just twenty-nine, he took command of the 69th Brigade of the 23rd Division, which was then serving on the Italian Front.
He handled his men with great skill, clearing the trenches to his right with his Company and bombers, and, after reaching the line allotted to the Battalion, entrenched himself and held on under heavy artillery fire during the 16th, 17th and 18th May.
[9][10] On the outbreak of the Second World War, Beauman returned to active service and was appointed Commanding Officer Northern Area with the British Expeditionary Force (BEF) in France, with the rank of (acting) brigadier.
He formed a small mobile force, known as "Beauforce", consisting of four Territorial infantry battalions that had been intended to defend communications and undertake pioneer work.
[13] Although supported only by a few field guns that had been under repair in base depots, some of them lacking sights, the division was ordered to defend a 55-mile (89 km) line defined by the small rivers Andelle and Béthune in Upper Normandy.