The current publication is based on the author's dissertation, "Léon Bonnat (1833-1922) portraitiste. Catalogue raisonné des portraits peints, dessinés et gravés," presented at the Sorbonne in 2015 This work is composed of an introductory section with an in depth analysis of the artist's work. There are discussions of Bonnat's training and career, the political and cultural background of the period, the artist's commissions, his patrons, and the art market.