There are quite a few Gehans here in St. Paul, Minnesota. My great-great grandfather, John Gehan, came to the U.S. from Ireland around 1855 (?). He had a grandson, John Gehan, who moved back to New York and became quite prominent in the shipping industry. I believe he died in the mid-1960's. My brother is named John Gehan. There are also a bunch of Gehans in Texas who build houses.