Events that occurred on 30 March
 On Earth
- 1936 - C.A. Furth (of George Allen & Unwin Ltd) writes a letter to J.R.R. Tolkien.
- 1940 - J.R.R. Tolkien writes Letter 38.
- 1953 - J.R.R. Tolkien and Edith move to 76 Sandfield Road.
- 1968 – The documentary Tolkien in Oxford is aired on the BBC.
- 1972 - J.R.R. Tolkien writes Letter 334.
- 2005 - Unsung Heroes of The Lord of the Rings is published.
 In Arda