Hamberg in Finland
i'm a Hamberg, too, but my family came from Finland. our family name is actually "Haanpaa", but my great-grandpa couldn't read or write when he arrived on Ellis Island and bought land in Michigan, so we've all been "Hambergs" ever since. like a lot of other scandinavian emigrants, he settled in the upper peninsula (Ironwood, MI/Hurley, WI).
his brother *did* get his name put down correctly when he came over, and there are apparently a bunch of Haanpaas somewhere in Massachussets.
i was surprised to learn that there's another "Hamberg" line down in SC, in Pendleton, near where i went to college. they had a family reunion at the Holiday Inn in Clemson once, and i was shocked to see my "unusual" last name up on a sign, spelled with an "e" and everything. it's a black family, though, so i doubt they're ethnically German, Swedish, or Finnish--but their ancestors might have been forced to take the name of their "owners" (not very nice to think about, but it unfortunately happened pretty often)--so there might be a link for you there.