Timeline
March 2016
WikiLeaks publishes the “Podesta Emails” (part of the DNC leaks attributed to Russian hackers).
Oct 28–31, 2016
4chan /pol/ users begin analyzing Podesta emails. Someone notices frequent mentions of “pizza,” “pasta,” etc. in casual correspondence.
Oct 30, 2016
First explicit “pizza = child” code claim appears on 4chan. A user pastes an unsourced Urban Dictionary entry claiming “cheese pizza” = child pornography.
Nov 1–3, 2016
Theory migrates to Reddit (/r/The_Donald → /r/pizzagate created Nov 4). Users compile “evidence” collages linking Comet Ping Pong Instagram photos, band logos, etc. to supposed pedophile symbols.
Nov 4, 2016
First mainstream mention: a Turkish newspaper (Sabah) and pro-Erdogan outlets run stories claiming the Podesta emails prove a U.S. pedophile ring.
Nov 7, 2016
Twitter account @pizzagate (now suspended) created; theory goes viral on Twitter.
Nov 2016
Infowars, David Seaman (YouTube), Brittany Pettibone, and others begin covering it heavily. James Alefantis’s Instagram (filled with normal hipster DC art-scene photos) is misinterpreted as occult/pedophile imagery.
Nov 21, 2016
Reddit bans /r/pizzagate for doxxing. Theory moves to Voat and 8chan.
Nov 27, 2016
New York Times publishes first major mainstream article describing it as “fictitious.”
Dec 4, 2016
Edgar Welch shoots up Comet Ping Pong. No basement is found (the building has no basement).
Dec 5–8, 2016
Comet Ping Pong receives hundreds of death threats; nearby businesses also targeted.
Jan–Mar 2017
Multiple law enforcement statements: DC Metro Police, FBI, and fact-checkers (Snopes, PolitiFact, FactCheck.org) all declare the theory baseless.
June 2017
Alex Jones/Infowars formally apologizes to James Alefantis and retracts all Pizzagate coverage (to avoid defamation lawsuit).
2020–present
Theory morphs into QAnon (“pizza” references become core QAnon lore). Some adherents still insist it was real despite zero arrests or evidence.