Events from the year 1866 in France.

• 31 May - Napoleon III announces the withdrawal of French forces in the French intervention in Mexico.
• 26 July - French evacuate Monterrey.
• 5 August - French evacuate Saltillo.
• 14 October - French troops land at Ganghwa Island, Korea as part of French Campaign against Korea for the execution of French Jesuit priests. It is the first military contact between Korea and a Western force.

• 31 October - Jacques Offenbach's opéra bouffe La Vie parisienne is premiered at the Théâtre du Palais-Royal in Paris.

• 17 January - Joseph Bernard, sculptor (died 1931)
• 29 January - Romain Rolland, writer, recipient of Nobel Prize in Literature (died 1944)
• 19 February - Louis-Henri Foreau, painter (died 1938)
• 17 May - Erik Satie, composer and pianist (died 1925)
• 23 May - Ellen Richards Ridgway, American golfer (died 1934)^[1]
• 6 July - Charles Mangin, general during World War I (died 1925)
• 13 July - La Goulue, dancer (died 1929)
• 4 August - Maurice Schutz, actor (died 1955)
• 7 September - Tristan Bernard, playwright, novelist, journalist and lawyer (died 1947)
• 21 September - Charles Nicolle, bacteriologist, recipient of Nobel Prize in Physiology or Medicine, 1928 (died 1936)

• 8 March - Siméon-François Berneux, Roman Catholic missionary killed in Korea (born 1814).
• 11 August - Philippe Buchez, author and politician (born 1796).