A lot of swedes have emigrants in the families even if they haven't done any research or know about them. Not strange as about 1,3 miljoner swedes emigrated during 1850-1930, about 300 000 came back. Maybe they left to make money to buy a farm when they came back. The rest stayed in their new homeland. Most of them emigrated to US but also to other countries as Canada, Russia, Australia or England.
Today 4 % of the US population count themselves of being swedes. Most of the probably not fullblood swedes as an american of today is a mix of people from all over the world.
Swedes-americans are all over North America there also Canada counts in. Most known that swedes settled down is in Minneapolis in Minnesota and the area around there. In Illinois is it Chicago, Rockford, Galesburg and Rock Island. They did as the immigrants of today in Sweden, settled down in the neigbourhood of other compatriot. As for an exampel that a lot of immigrants from the parish of Floby (R) and the area around, settled down in Galesburg, Knox Co, IL.
It was common that the immigrant traveled to a familymember who already established her-/himselfs in the new country.