Events that occurred on 15 January.
 On Earth
- 1957 - J.R.R. Tolkien is interviewed by Ruth Harshaw for the NBC radio program "Carnival of Books".
- 1965 - Actor James Nesbitt is born.
- 1967 - Philip Norman's interview with J.R.R. Tolkien is published in The Sunday Times Magazine and in The New York Times Magazine.
- 1970 - Musician Charles Deenen is born.
- 1972 - The Tolkien Society holds a general meeting and becomes formally constituted.
- 2005 - The second day of the first "The One Ring Celebration".
 On Arda
- T.A. 3019:
- The Fellowship of the Ring find the Chamber of Mazarbul and Balin's Tomb. Gimli takes the Book of Mazarbul.
- Attack of the Orcs and the Balrog. Gandalf destroys the Bridge of Khazad-dûm and falls with Durin's Bane.
- The rest of the Fellowship exits Moria and enters Dimrill Dale.
- Gimli, Frodo and Sam gaze in Mirrormere.
- Haldir, Rúmil and Orophin meet the Fellowship. They sleep on flets.
- Orcs pass through Lothlórien.