Charles was born 8th March 1885 in Kobe, Japan, the eldest son of the Right Reverend Hugh James Foss, Bishop of Osaka.

He enrolled into the Royal Military Academy at Sandhurst in 1902 and was commissioned as a Second Lieutenant in the Bedfordshire Regiment in 1904. Charles Foss was serving in the 2nd Battalion of the Bedfordshire Regiment in South Africa when the war broke out and the battalion made it to the Western Front in time for the First Battle of Ypres. He was one of only four Officers to survive the battle during which he won his Distinguished Service Order (medal).

Second Lieutenant Collings-Wells was commissioned into the Bedfordshire Regiment on 14th March 1904 having previously served with the Hertfordshire Militia. He became a Lieutenant in September 1904 and Captain in January 1907. On the outbreak of war he was recalled to the colours and arrived in France with the Bedfordshire Regiment on the 22nd August 1914, where he served in the 2nd Battalion once they had arrived from South Africa. By October 1916 he was promoted to acting Lieutenant-Colonel in command of the 4th Battalion and remained at that post until his death.