Events that occurred on 11 December.
 On Earth
- 1914 - Tolkien writes Ferrum et Sanguis: 1914.
- 1955 - The fifth episode of 1955 radio series of The Fellowship of the Ring airs on the BBC Third Programme.
- 1971 - J.R.R. Tolkien writes a letter to George and Moira Sayer.
- 2014 - The Hobbit: The Battle of the Five Armies is released in New Zealand.