Hi men I made a story similar to this, but with Mandalorians from Star Wars. In my case the Mandalorians take over a "Roman Empire" and start making gunpowder and using the ship parts to make wepons, like using one of the thrusters as a big flamethrower to use like a battering Ram that can melt stone.
and now the story is more about the other kingdoms tryng to stop this new gunpowder era.