A Company, Heavy Branch Machine Gun Corps, the forerunner of the First, was formed under Major C M Tippetts, South Wales Borderers, at Elvesdon, Norfolk and moved under his command to France in October 1916. At the end of the year the expanded Company became 'A' Battalion. For his gallantry at Ypres in October 1917 Captain C Robertson was posthumously awarded the first Victoria Cross for the Tank Corps. In the following month the Battalion took part in the Battle of Cambrai with the other eight original Battalions of the Corps, and Captain R Wain won the Battalion's second Victoria Cross.
On 24 April 1918 the victor of the first tank versus tank engagement at Cachy was Lieutenant F Mitchell's tank No 1 of A Company. Later in the year on 8 August the Battalion took part in the Battle of Amiens in which over 600 tanks were involved and during which an advance of up to 20 miles was achieved. Unfortunately, the cost to the Battalion was high; nine out of ten tanks in 'A' Company of the Battalion were destroyed.