Quinn studied painting at the Pennsylvania Academy of the Fine Arts, Philadelphia, under Thomas Eakins and sculpture in Paris under J.ÄA. Injalbert. Among his early efforts are a statue of John Howardÿdone for Williamsport, Pennsylvania, in 1905 and reliefs for a battle monument at King's Mountain, South Carolina, executed in 1908. His monument to General John C. Pemberton was erected at Vicksburg in 1917. One of his best known sculptures is the statue Edwin Booth as Hamlet commissioned by the Players' Club for Gramercy Park in New York and dedicated in 1918. Besides painting a number of portraits, he modeled many portrait busts, including one of Edgar Allan Poe for the Poe Cottage in Fordham, New York. He was a member of the National Sculpture Society, the Century Club, and the Players' Club, among others. He occasionally exhibited his work at the National Academy, beginning in 1891. His life ended in suicide.
