. . .she tended Hungarian wounded returning from the Russian front and casualties wounded in American bombing raids. (The Telegraph)
When there are modifiers before 'wounded,' is it used without ‘the’ to denote 'wounded people'?
wounded can be both an noun and an adjective.
they rounded up the wounded for treatment - here it is a noun meaning the wounded ones.
they rounded up the wounded cats for culling - here it is an adjective to modify cats.
"She tended the Hungarian wounded" means, all the wounded Hungarians can be considered as one group and she tended the people in that group. (Not necessarily every single person in the group.) "She tended Hungarian wounded" means she tended to some individual wounded Hungarians, but says nothing about whether there were any others she didn't attend to.
To put it more simply, "the wounded people" is different from "wounded people" and adding "Hungarian" doesn't change that.