The Infantry Division in the Great War varied significantly from its commencement in 1914 through to the Armistice in 1918.
The 1914 establishment as the British Expeditionary Force went to France consisted of three Brigades of four Infantry Battalions each, plus supporting arms and services. The numbers of Machine Guns within the Division was 2 per Battalion, within the Machine Gun Section - a total of 24 guns. Depending on its specific establishment, the Divisional Cavalry Squadron may also have had a Machine Gun Section attached; although this is unlikely.
In 1915, a number of changes were made to the establishment of the Division, however the only change to the MG establishment was the increase from two guns within the Machine Gun Section to four; therefore, doubling the firepower of the Division to 48 guns.
The establishment of the Machine Gun Corps in October 1915 saw the establishment of centralised Machine Gun assets in the form of Brigade Machine Gun Company's. The Vickers MGs within the Battalions were replaced with Lewis Light Machine Guns at a ratio of 12 per Battalion
Further enhancements took place in 1917 with the formation of a fourth MG Company of a further 16 guns to act as a Divisional asset. This took the total number of Vickers MGs within the Division to 64.
Further centralisation took place in 1918 with all Vickers MGs becoming Divisional assets through the formation of a Machine Gun Battalion comprising the four Machine Gun Companies; the number of guns remained at 64. Additional rationalisation took place with the reduction of the number of Infantry Battalions within the Brigades from four to three.