Plus then you have to take into account that firstly, thralls were tken from here and there, though mostly from Ireland, but also from Slavonic and Baltic populations. Sometimes more from one or the other (south-eastern Skåne for example had relations with baltic tribes that reach very far back). The biggest foreign population in Sweden are the Finns, some of them having lived there for longer than others. Then there has been immigration from Germans, lots of Germans. Stockholm is pretty much founded by them. Then the Wallonians which were skilled workers, came quote a few of them. And some french. Some balts, Estonians mostly, because of all kinds of Russian/Soviet invasions. Then of course the occasional Frenchamn, Dutch, Italian, Englander and Scotsman and what have you, but not so many (more with the nobility). That's all I could think of from the top of my head, but out of all these, Germans, and the Finns in the northern parts, are probably the largest foreign influx.