Doyle became a sculptor of marble and bronze monuments of historical figures including Civil War participants and other prominent persons. He studied in Italy at the National Academies at Carrara, Rome, and Florence and was a member of the Royal Raphael Academy. His work can be found throughout the United States including in Washington, D.C., Missouri, Alabama, New York, Ohio, Indiana, Georgia, and Mississippi.
In New Orleans, where he was active in 1882 and 1883, he created a trio of important sculptures of Confederate States Armygenerals. These are: the city's iconic figure of General Robert E. Lee at Lee Circle, dedicated in 1884 and removed by Mayor Mitch Landrieu on May 19, 2017; the massive bronze General Beauregard Equestrian Statue at the entrance to City Park (1915), removed on May 16 of 2017 and placed in a city junk yard; and the bronze statue of General Albert Sydney Johnston atop the Army of the Tennessee cenotaph in Metairie Cemetery (1887). According to Leonard V. Huber, author of New Orleans Architecture: The Cemeteries, Doyle's finest work is "Calling the Roll" (1885), a marble sculpture of an unknown Confederate soldier. "Calling the Roll" stands before the General Johnston bronze monument in Metairie Cemetery.
A Doyle marble statue of Margaret Haughery, a New Orleans woman who devoted her life to the poor, was erected in 1889, the first monument to honor a female philanthropist in the United States.[citation needed]
"Portrait of Benjamin Harvey Hill standing with his right hand resting on a podium and his left hand pulling back the side of his overcoat, and resting on his left hip."[11]
Adjacent to the mausoleum set up by Association Army of Tennessee, Louisiana Division, C.S.A with Doyle's Equestrian Statue of General Albert Sidney Johnston. The sculpture was a gift of Charles T. Howard. The sculpture depicts a Confederate soldier calling role; the soldier's face was carved based on the photography of New Orleans Confederate Soldier William Brunet.
Sculpture: approx. 5 ft. 4 in. × 6 ft. 5 in. × 6 in.; Base: approx. 9 ft. × 26 ft. × 30 ft. 2 in.
"A uniformed nineteenth century-era soldier stands at the center of the relief, holding a flagpole in his bent proper right arm and a rifle in his proper right hand. An eagle overhead bears a banner in its mouth on which is written the State motto. The decorative scrolling includes corn and wheat stalks."[29]