My great great grandfather, Johannes Ulrich Kreis, known as John in America, was born in Switzerland of German heritage. He came to America in 1866 on the ship Arago leaving from Havre. On his naturalization card, several US censuses, and his citizenship document, John put Switzerland as his birthplace.
I am trying to find the district/village in Switzerland where he was born. The only clue that I have is on FamilySearch, I found a majority of men named "Johannes Ulrich Kreis" born in Thurgau. In the international white pages, I found many living Johannes Ulrich Kreis men in Thurgau.