For the first four years of Wikipedia's existence, at random times known only to him, Jimbo decreed an official Wikipedia holiday. These are to be celebrated annually in the manner described in the proclamation. After a long break, the tradition was briefly resumed in 2012. Note that each proclamation begins with Jimbo proclaiming "in his usual authoritarian and bossy manner"—meant to poke fun at the general impression that he's somehow the GodKing of Wikipedia, which he proclaims in his usual authoritarian and bossy manner that he isn't. This is just his fun tradition.
- January 15 since 2001 – Wikipedia Day (not actually proclaimed by Jimbo, just universally acknowledged)
- January 25 since 2002 – Magnus Manske Day
- October 31 since 2003 – Tim Starling Day
- June 1 since 2004 – Brion Vibber Day
- April 20 since 2012 – Justin Knapp Day
Wikipedia holidays are a part of the Wikipedia:Awards system.