 He prospered as a merchant in New Bedford, Massachusetts, but had a political squabble and left for New York.He, along with Joseph Grinnell, controlled a potent shipping firm named Fish & Grinnell – later Grinnell, Minturn & Company – which had its beginnings in his efforts to expand his whale oil market.In 1812, he became a director of Bank of America, founded after the charter of the First Bank of the United States was not renewed.