One of the first large-scale implementations occurred in the United States during WWI, when the military used an IQ test to sort recruits and screen them for officer training.
Now, that change could be due in part to those tougher controls, the efforts to identify and stop potential recruits here in the U.S. or elsewhere in the West, from joining the fight in the Middle East.
Well, they were mostly vicious, brutal ex-convicts, or raw recruits, and elderly men, the officers who commanded them were all untrained as military men.