Of course there were always safety rules, from the earliest days of firearms:
"Keep your powder dry."
"Never draw unless to shoot, never shoot unless to kill."
Plenty of others. Some of the rules were applicable to only one kind of gun ("Keep your muzzle above the head of the tallest person on the range") or to only one set of circumstances ("Stay behind the yellow line while others are downrange"). Some would apply only to range work, some only to field work, some only to guns with external safeties, some only to revolvers or only to single-action semi-autos or only to double-action only handguns...
There were a lot of rules, but no uniformity.
Jeff Cooper deserves a great deal of credit for being the first to perceive the need for truly universal safety rules, rules that would apply to all firearms at all times. He's the first one who boiled all of the various rules about firearms down into just four rules -- rules that are simple enough that even a child could follow them, rules that provide an overlocking safety system, rules that pretty well everyone else in the gun world has acknowledged as simple and basic and enough.
You might not think that's a big deal, but there's a lot of genius that went into those four simple rules. Complexity is easy; simplicity is difficult. Jeff Cooper made firearms safety more simple at a time when firearms were becoming more complex. That's genius.
pax
There were others who might have (I question that part)
-- But, after all, they didn't do it! -- Grace Stricker Dawson
