Events that occurred on 11 August
 On Earth
- 1955 - During a holiday to Italy, J.R.R. Tolkien and his daughter Priscilla visit a mass at the church of Santa Chiara.
- 1966 - The Christian Science Monitor (11 August 1966), including an interview with J.R.R. Tolkien by Daphne Castell, is published.
- 1978 - Mythcon 9 in West Sacramento, California.
- 1984 - Mythcon 15 at Mills College in Oakland, California.
- 1986 - Mythcon 17 at California State University in Long Beach.
- 1997 - Mythcon 28 at Pepperdine University in Malibu, California.
- 2005 - The Tolkien Society's Tolkien 2005 conference in Birmingham, England.
- 2007 - Omentielva Tatya - 2nd International Conference on Tolkien's Invented Languages in Antwerp, Belgium.
- 2011 - Omentielva Cantea - 4th International Conference on Tolkien's Invented Languages in Valencia, Spain.