- Dec 3 Allen Thomas, American Brigadier General (Confederate Army), dies at 76
- Dec 8 Oscar II Frederick, King of Sweden (-1907)/Norway (-1905), dies
William Thomson
Dec 17 William Thomson, 1st Baron Kelvin, Irish-Scottish mathematical physicist (Kelvin Scale) and engineer (transatlantic telegraph), dies of a chill at 83
- Dec 21 Oskar Lassar, German dermatologist (public baths), dies at 58
- Dec 23 Pierre Janssen, French astronomer, discovered helium, dies at 83
- Dec 24 Isidor Feinstein "Izzy" Stone, journalist (IF Stone's Weekly), dies
- Dec 31 Jules de Trooz, Belgium politician, Prime Minister of Belgium (1907), dies in office at 63