The first edition of the encyclopaedia was compiled over a number of years by antiquarian bookseller Ben Weinreb and by the historian Christopher Hibbert, and was revised in 1993, 1995, and 2008. It has around 5,000 articles, supported by two indices—one general and one listing people, each of about 10,000 entries—and is published by Macmillan.
In 2012, an app was developed by Heuristic-Media, and released as London—A City Through Time. Toby Evetts and Simon Reeves, partners in Heuristic-Media, discussed the development of the app with The Guardian in 2013, describing how 4,500 entries had to be plotted onto a guide map by hand.
The encyclopaedia builds on a number of earlier publications, including:
- Survey of London by John Stow, 1598.
- The Survey of London — a multi-volume publication originated in 1894 by Charles Robert Ashbee, adopted first by the London County Council, then the Greater London Council, and now domiciled with English Heritage.
- Handbook for London by Peter Cunningham, 1849.
- London Past and Present by Wheatley and Peter Cunningham, 1891.
- Jones, Philip (5 July 2012). "New app 'reinvents' London Encyclopaedia". The Bookseller. London. Retrieved 16 September 2014.
- "A unique guidebook: The city beckons - A multimedia compendium of 2,000 years". The Economist. 30 June 2012. Retrieved 16 September 2014.
- "How we made the London: A City Through Time app". the Guardian. 13 December 2013. Retrieved 16 September 2014.
- Wilder, Robyn (24 August 2014). "11 Rather Splendid Facts You May Not Have Known About London". BuzzFeed. Retrieved 16 September 2014.