Before the invention of the gun people killed in a variety of ways:
knives
poison
walk the plank
hanging
pulled apart by horses
2 x 4, or something similar, in the back of the head
arson
strangulation
pushed: out of a window, off a cliff/boat, into quicksand, into a fire, in the way of horses, wagons, etc.
by a gladiator
by having to listen to Ethel Merman sing "There no business like...: oops, before their time
I think you've got the gist of it.
I just happened to check out the heyjackass site today, and nearly 15% of the 77 homicides in ChiTown this year have been something other than guns - knives, or blunt force trauma.
Before the black powder age, people that championed against the top weapon of the day usually ended up skewered or impaled by something pointy, spiky, and generally unpleasant.