Born in Belfast, Ireland of French and Irish parents. He began the study of art under the French artist Sauveur. At fourteen, his parents having died, and he immigrated to America with an aunt, and settled in Baltimore, Maryland. He studied with David A. Woodward at the Maryland Institute for the Promotion of Mechanic Arts, and in 1860 won the Peabody Prize. During the Civil War he was a draftsman for the Confederate Navy, and later made topographical maps for Gen. Robert E. Lee. After the war McArdle married and eventually settled in Independence, Texas, where he taught art at Baylor Female College for many years. He worked with men of Hood's Texas Brigade on the historical canvas Lee at the Wilderness (1869-70) and became interested in Texas history. He won a commission to paint a full-length portrait of Jefferson Davis (1890) for the Capitol as well as several portraits of Sam Houston, and other notables, and stirring battle scenes. (Dawn at the Alamo (1876-1905) The Battle of San Jacinto (completed 1898), which hang in the Senate Chamber in the Texas Capitol) Sam Houston (1902) and The Settlement of Austin's Colony (1875), which hangs in the hall of the House of Representatives in the Texas Capitol. In later years he suffered from financial hardships, McArdle died in San Antonio on February 16, 1908. Nineteen years after his death, the legislature of Texas paid his heirs $25,000 for Dawn at the Alamo and The Battle of San Jacinto.