Britain was the only one of the major combatants to begin the war without a large standing army. The other nations conscripted men into their armies but Britain had a comparatively tiny army comprised only of people who had voluntarily enlisted. This army was too small for the war that Britain found itself fighting. Initially the British authorities appealed for volunteers to make up the army’s numbers. That initially yielded a large number of men but as the carnage of the conflict became more apparent it became harder to find sufficient volunteers.
Earlier this year Britain began to conscript unmarried men into the army. Now the recruiters’ net is widened as married men too find themselves summoned to the colours. This may be because of fears that shirkers were entering into ill-starred marriages as a way of avoiding their martial duty.
Conscription continues to apply only to England, Scotland and Wales. Given the recent rebellion in Dublin it seems wise to not provoke the Irish.
Daddy, what did you do in the Great War? (Highfield Modern World History)
New recruits (BBC News)