Going to Europe in 1835 Healy studied under Baron Gros in Paris and in Rome. He received a third-class medal in Paris in 1840, and one of the second class in 1855, when he exhibited his "Franklin urging the claims of the American Colonies before Louis XVI."
Among his portraits of eminent men are those of Webster, Clay, Calhoun, Guyot, Seward, Louis Philippe, and the presidents of the United States from J. Q. Adams to Grant--this series being painted for the Corcoran Gallery, Washington, D.C..
His large group, Webster replying to Hayne, containing 180 portraits, is in Faneuil Hall, Boston, Mass. He was one of the most prolific and popular painters of his day. He died in Chicago, Illinois, on the 24th of June 1894.