The brother of the painter William Stanley Haseltine and uncle to the sculptor Herbert Haseltine, James Henry Haseltine was a native of Philadelphia. James studied sculpture there under Joseph A. Bailly, and exhibited works—apparently, mostly in marble—at the Pennsylvania Academy of the Fine Arts beginning in 1855. He went to Italy and France for further study about 1857, but returned in 1861 to serve for two years in the Civil War. After the war he again went abroad and opened a studio in Rome, where he was to spend the rest of his life.
Rome was a fertile ground for artists at mid-century. Virtually every major artist went there at some point, and some established permanent homes and studios. When Haseltine arrived in the fall of 1857, the American sculptors Harriet Hosmer, Chauncey B. Ives, Joseph Mozier, William Henry Rinehart, and William Wetmore Story had flourishing studios in Rome. The poets Robert and Elizabeth Barrett Browning were in residence, and Nathaniel Hawthorne was at work on The Marble Faun. Haseltine quickly assimilated himself into this community, producing both ideal works and portrait busts in the Neo-Classical mode in his Roman studio. There he entertained guests and led a productive career until about 1880, when he appears to have removed to France. He married the following year, and remained in France until about 1903, when he returned to Italy, settling in Florence, where he died four years later.