Events that occurred on 25 May.
 On Earth
- 1939 - Actor Ian McKellen is born.
- 1944 - J.R.R. Tolkien writes Letter 71.
- 1965 - J.R.R. Tolkien writes Letter 271.
- 1968 - "In the Footsteps of the Hobbits", an interview with Tolkien, is published in the Birmingham Post.
- 1972 - J.R.R. Tolkien writes Letter 337.
- 2004 - The theatrical edition of The Lord of the Rings: The Return of the King is released on DVD.
 In Arda
- There are no known events for this day.