He wrote a Histoire de la Philosophie, translated into English in seven volumes.
This work inspired Frederick Copleston's own History of Philosophy (1946–1975), initially comprising nine volumes.
In 1908 he received his doctorate at the Sorbonne with a dissertation about Philo of Alexandria.
In 1914 Bréhier became a sub-lieutenant in the 344th Infantry Regiment; later he was made knight of the Légion d'honneur.
[2] He has been called "the sole figure in the French history who adopts an Hegelian interpretation of Neoplatonism",[3] but also a Neo-Kantian opponent of Hegel.