Events that occurred on 19 September.
 On Earth
- 1916 - Writer Terence Tiller is born.
- 1931 - J.R.R. Tolkien, C.S. Lewis and Hugo Dyson have dinner, followed by a conversation that ran until 4 a.m. the following morning that was essential for Lewis's conversion to Christianity.
- 1944 - J.R.R. Tolkien writes a postcard to G.E. Selby.
- 1956 - J.R.R. Tolkien writes a letter to Terence Tiller.
- 1962 - J.R.R. Tolkien writes a letter to Alina Dadlez.
- 1982 - The article "The Return of Tolkien" is published in The Sunday Times Magazine.
- 1986 - Oxonmoot 1986 at Oxford Town Hall.
- 1993 - Oxonmoot 1993 at University College.
- 1997 - Oxonmoot 1997 at Exeter College.
- 2003 - Oxonmoot 2003 at St Hugh's College.
- 2004 - Oxonmoot 2004 at St Hilda's College.
- 2004 - The Lord of the Rings Symphony at Mortensen Hall in Hartford, Connecticut.
- 2020 - Oxonmoot 2020 held online due to the Covid-19 pandemic.