Gueniffey obtained his PhD in history in 1989 with a thesis on suffrage during the French Revolution, and was hired at the École des hautes études en sciences sociales (EHSS), where he has been a full professor since 2001.
[2] From 2006 to 2008, he directed the Centre de recherches politiques Raymond Aron, founded by François Furet, of whom Gueniffey was a disciple.
[3] Gueniffey collaborated on the Critical Dictionary of the French Revolution, directed by Furet and Mona Ozouf in 1988.
[4][5][6] Gueniffey, writing in Le Point magazine, criticized the 2023 film Napoleon as rewriting history in a "very anti-French and very pro-British" manner.
[7] In 2013, Gueniffey was awarded the Grand prix de la biographie politique for Bonaparte which included 10,000 euros in prize money.