Speaking of the Ottoman empire, when I watched a Turkish show recently I was surprised to hear a number of words I had no idea were Turkish origin. (Well, could be the other way around too I guess. But they sounded Turkish.) Sanduk, čizma, budala, paramparčad, kapija, sandžak, inat, kutija, ajde just off the top of my head.

The German connection is definitely there. There was even a transliterated word used for people working abroad: "gastarbajter," from German Gastarbeiter. And it was used for anyone working abroad, no matter where :-)

Edit: https://en.wiktionary.org/w/index.php?title=Category:Serbo-C... . I can't believe "boja" is borrowed.