The Last of the Spartans caught the eye of William E. Cramer, then editor of the Evening Wisconsin newspaper. When the World's Fair closed, Cramer bought the sculpture for the Layton Art Museum in Milwaukee. Trentanove began to visit Milwaukee, taught classes at the Layton School of Art and eventually opened a studio in Milwaukee.
He became an American citizen, but besides working in Milwaukee, he maintained his studio in Florence, where his favored foundries were located. His American citizenship made it easier to import his bronze castings.
In 1894, Trentanove was commissioned for a statue of Father Jacques Marquette for Statuary Hall in the United States Capitol to represent Wisconsin. Trentanove would go on to do more sculptures of Marquette for various locations. In 1907, while the Soldier's Memorial was being placed in Oshkosh, a sculpture of Governor Nelson Dewey was being placed in Lancaster, Wisconsin and a monument to President William McKinley was placed in Somerville, New Jersey.
Numerous other public sculptures by Trentanove are located around the country, and numerous other works are not on public display. A bust of John Hicks is on display at the Oshkosh Public Library.
When he retired, Trentanove returned to Italy, where he died on March 13, 1937.