Events that occurred on 17 February.
 On Earth
- 1894 - Hilary Tolkien, J.R.R. Tolkien's brother, is born.
- 1934 - Actor Barry Humphries is born.
- 1919 - Hilary Tolkien returns home after the War.
- 1938 - J.R.R. Tolkien writes Letter 23.
- 1963 - J.R.R. Tolkien writes a letter to Julie Cape.
- 1991 – The third day of the first "Colloquium on the Languages of Middle-earth" at the house of E.L.F. member Bill Welden.