Mandatory conscription was developed by revolutionary France, and after being smashed by the French, the Prussians (whose military was arguably the highest quality in Europe) adapted the system into the form generally known today (every adult male has to provide N (usually 1-3) years of mandatory military service). The US never had anything like this system: there was mandatory conscription during the civil war, and the draft (a lottery-based system rather than universally compulsory) was enacted in peacetime in 1940.