Simmons was born in Webster, Maine. He spent most of his childhood in Bath, Maine and Lewiston, Maine. He attended Bates College (then called the Maine State Seminary) in 1858. Simmons started sculpting and painting during childhood. He studied with John Adams Jackson.
During the last two years of the American Civil War, he moved to Washington, D.C. and modeled 24 portrait medallions of President Abraham Lincoln, his Cabinet, and generals and admirals. The Union League of Philadelphia purchased most of the medallions. In 1867 Simmons received an honorary A.M. from Bates College and from Colby.
Simmons went to live in Rome in 1868, but returned several times. Among his portrait busts are those of David D. Porter, James G. Blaine, Francis Wayland, and Ulysses S. Grant (1886). He is said to have made a female statue of The Wanderer, meant to depict a Jewess wandering in the desert. He died in Rome, aged 74, and is buried in the Protestant Cemetery.
Selected works
Bust of Oren Cheney (1861?), Bates College, Lewiston, Maine. Simmons sculpted this while a student at Bates College.
Soldiers' Monument (1866–68), Kennedy Park, Lewiston, Maine.
Soldiers and Sailors Monument (1867–69), Bellingham Square, Chelsea, Massachusetts.
Peace Monument (formerly Naval Monument) (marble, 1877), United States Capitol Grounds, Washington, D.C., Edward Clark, architect. The figures atop the monument are titled "Grief and History."
Bust of Vice President Adlai E. Stevenson (marble, 1894), United States Senate Vice Presidential Bust Collection.
Ulysses S. Grant (marble, 1899), United States Capitol Rotunda. Simmons's 1894 statue, showing Grant in civilian clothes, was rejected for the U.S. Capitol. It is now in the Portland Museum of Art.
Bust of Vice President Charles W. Fairbanks (marble, 1905), United States Senate Vice Presidential Bust Collection.
Governor Francis Harrison Pierpont (marble, 1910), National Statuary Hall Collection (representing West Virginia).