[1] He later entered the Royal Military College, Sandhurst, from where he was commissioned as a second lieutenant into the South Wales Borderers on 9 October 1907.
[3] Williams fought in the First World War and received a promotion to the rank of captain on 22 October 1914.
[4][1] After seeing action in the Gallipoli campaign,[5] and after being awarded the Military Cross (MC) in 1916,[6] he served as a staff officer with the 30th Division on the Western Front, earning recognition with his appointment as a Companion of the Distinguished Service Order (DSO).
[7] The citation for his DSO reads:[8] At Menin, on October 14th, 1918, he made a very bold reconnaissance of the river crossings in face of considerable shell and machine-gun fire and forward of all our infantry posts, thus enabling a bridge to be thrown over at the earliest opportunity.
[9][5] He became commander of the 160th Infantry Brigade, part of the 53rd (Welsh) Infantry Division, in February 1939[10] and, in April 1940, seven months after the outbreak of the Second World War, went with his brigade to Northern Ireland where it was mainly involved in anti-invasion duties and exercises training to repel a potential German invasion of Northern Ireland.