>>280004396
Vigilantes explained it already during Makoto's exposition. The first heroes were Vigilantes and were hundreds but the government wanting to decide who is a "hero" and who isn't, decided to sanction it as a way of control and created the concept of "villain" to mark anyone who didn't conform to the government's agenda. They took the 7 strongest heroes and apprehended all the others who didn't measure or wouldn't bow down to the govs.
Hawks and his agency were also created to "disappear" those who become troublesome to the government but can't be publicly executed.