During the Second World War, as you might expect, the UK imposed a regime of universal conscription.
From the outbreak of war in 1939, unless you were medically unfit or in a reserved occupation – one that was considered vital for the continuing function of the economy and the war effort – every male between the ages of 18 to 41 had to join one of the services.
In December 1941, that was expanded to include men up to the age of 51, and all unmarried women and all childless widows between the ages of 20 and 30, though the women were excused combat roles.
But when the war ended in 1945, conscription didn’t end with it.
Britain found itself still with huge overseas interests to defend, not just the empire, but now also it had to garrison occupied Germany and Japan. Instantly there was the threat of aggression from an expansionist USSR and although the term Cold War had yet to be invented, as early as March 1946, Churchill was speaking of an Iron Curtain descending across Europe.
In addition there were actual physical communist insurrections in Greece and Burma – and in Vietnam of course, though thankfully we side-stepped that one.
When India was granted independence in 1947, Britain lost access to the huge Indian Army that had helped us garrison the world, leaving a big hole in our resources.
So from 1949, a new form of conscription was…