When was the first encyclopedia created?

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