Crossbow as in the mass-produced hand-held type, Aristo. Not the siege weapon type. Basically: an era when, for ranged combat other than siege weaponry and Evoking, you would be limited to things that take years of practice to become a danger to more than yourself with. i.e. Bows, slings, throwing knives, etc. Not crossbows, guns, reliable cannons, etc.

Don't forget that since this isn't earth, eras can be twisted a little.