The oldest substantial encyclopedia is Zedler's Universal-Lexikon. (There are also a handful of shortish, single-volume encyclopedias dating from about 1709 onwards). Zedler appeared in 64 volumes (plus a 4-volume supplement) between 1732 and 1754. It was published by Johann Heinrich Zedler and appeared in Leipzig and Halle (in Germany). Most of the contributions were written by professors at these two universities. As is customary the articles are anonymous. Despite the fact that the work contains some plagiarism and a number of errors, it was a very remarkable achievement and represented a substantial investment. Joncey
Golden Book Encyclopedia was created in 1959.
Croatian Encyclopedia was created in 1999.
Dinosaur Encyclopedia was created in 2001.
Yongle Encyclopedia was created in 1408.
The Grocer's Encyclopedia was created in 1911.
Encyclopedia Americana was created in 1902.
Encyclopedia of Sound was created in 2001.
Klein's encyclopedia was created in 1898.
WWE Encyclopedia was created in 2008.
Conspiracy Encyclopedia was created in 2005.
Catholic Encyclopedia was created in 1907.
Doosan Encyclopedia was created in 1982.