He obtained his bachelor's degree at Williams College in 1920, and graduated with Phi Beta Kappa honors, after qualifying as a balloon pilot in the U.S. Army Air Service and as a second lieutenant in 1917–1919.[1][2] In 1930, Labaree wrote and published a work entitled, Royal Government in America: a Study of the British Colonial System before 1783,[3] for which he received the Justin Winsor Prize of the American Historical Association.While still working for his doctorate under the tutelage of Professor Charles McLean Andrews at Yale University with his thesis on Royal Government in America, Labaree was appointed an instructor in history in 1924.In 1954, he began his work, sponsored jointly by Yale University and the American Philosophical Society as editor in chief of The Papers of Benjamin Franklin, the first fruit of which was his 1956 book Mr.[4][5] Labaree's exemplary work on the Franklin Papers consolidated his reputation for the highest standards of documentary editing with thoroughness, accuracy, and clarity of explication.