Taking his advice, Peixotto went to France in 1888 and studied at the Académie Julian under the tutelage of Jean-Joseph Benjamin-Constant, Henri Lucien Doucet and Jules Joseph Lefebvre.

Although he frequently returned to the United States to work, the house in Fontainebleau served as his primary residence for the remainder of his life.

[5] During World War I, Peixotto served as a captain in the United States Army Corps of Engineers, director of the Section of Painting, and one of eight official artists attached to the American Expeditionary Force,[9] whose job was to create a visual record of events.

After the war, he remained in France as director of the United States Army's art-training center, which merged into the École des Beaux-Arts in 1923.

Peixotto remained as the chair of the school's American Committee, while simultaneously serving as the director of the mural department of the Beaux-Arts Institute of Design in New York, a position he held from 1919 through 1926, when he left to focus on his own work.