British Divisions
At the start of the Battle, each British infantry division consisted of over eighteen thousand men. Each division was divided into three brigades, which had four battalions each. The armies associated with the Battle of the Somme were the Third, Fourth and the Reserve (later the Fifth) armies.
Of those British infantry divisions that took part in the battle, the men that populated them were either part of the standing Regular Army, the Territorial Army, or Kitchener's New Army, following recruitment at the start of the War in 1914.
In addition there were cavalry men from India; Infantrymen and artillerymen from Australia, New Zealand and Canada.
Official British casualties for the Battle of the Somme (1st July to 18th November 1916) was four hundred and sixteen thousand, six hundred and fifty four men. The number of men killed or fatally wounded is considered to be in the region of one hundred and twenty five thousand.
The daily average of British Army casualties from one hundred and thirty nine days of battle was nearly three thousand men a day.