29 July - Physicist Augustin-Jean Fresnel submits his prizewinning "Memoir on the Diffraction of Light" to the French Academy of Sciences, precisely accounting for the limited extent to which light spreads into shadows, and thereby demolishing the oldest objection to the wave theory of light.
5 October - Claudine Thévenet (known as Mary of St. Ignatius) founds the Roman Catholic order Religieuses de Jésus-Marie ("Religious of Jesus And Mary") in Lyon.
30 November – The Allied Occupation of France (1815-1818) ends as the last troops depart in line with the agreement at Aix-la-Chapelle.