Treyarch was founded by Peter Akemann and Don Likeness in 1996 and acquired by Activision in 2001. The studio wasn't originally dedicated to the Call of Duty franchise when it developed with Gray Matter Interactive Studios Call of Duty 2: Big Red One released in 2005. Treyarch and Gray Matter then merged together and the studio released Call of Duty 3 the next year, in 2006. Both Big Red One and Call of Duty 3 used an in-house engine called Treyarch NGL based on the Id Tech 3 engine used in the first Call of Duty.
In 2008, Treyarch released Call of Duty: World at War using the IW engine from Call of Duty 4: Modern Warfare. It was the first Call of Duty game by Treyarch released on PC. After World at War, Treyarch was entirely dedicated to the Call of Duty franchise and became the second primary studio, alternating with Infinity Ward.
In 2010, Treyarch released Call of Duty: Black Ops set during the Cold War. The game was a success, earning $360 million on its launch day and $650 million within its first five days of release, surpassing records held by Call of Duty: Modern Warfare 2. After a month and a half, Black Ops crossed $1 billion worldwide. A year later, Treyarch assisted Infinity Ward and Sledgehammer Games with Call of Duty: Modern Warfare 3, they also ported the Wii version of the game. In 2012, Treyarch released Call of Duty: Black Ops II set place in the near-future in 2025, with some parts of the campaign set in the 1980's. The game was very successful and broke several records held by Call of Duty: Modern Warfare 3, grossing over $500 million on its launch day and became the fastest-grossing entertainement product to reach $1 billion in 15 days. Both records were later broken by Grand Theft Auto V in 2013.
In 2014, Dave Anthony, director of Black Ops and Black Ops II campaigns, left Treyarch. The same year, Jimmy Zielinski, Creative Director for the Zombies mode since Black Ops, left the company and was replaced by Jason Blundell.
Treyarch released Call of Duty: Black Ops III in 2015, which set place in the far future in the 2060's and the 2070's. The game grossed over $550 million within its first three days of release. Black Ops III became one of the best-selling games of the eighth generation of consoles. Treyarch also assited Infinity Ward during the developement of Call of Duty: Infinite Warfare in 2016. The same year, Mark Lamia became Chairman of Treyarch and Dan Bunting, Jason Blundell and Mark Gordon became co-Studio Heads.
In 2018, Treyarch released Call of Duty: Black Ops 4 which featured the first Battle Royale mode of the series, outside of Call of Duty Online only available in China, Blackout. Black Ops 4 grossed over $500 million within its first three days of release.
On August 4th, 2020, Treyarch confirmed that they were developing the next major Call of Duty title, Call of Duty: Black Ops Cold War alongside Raven Software.  It was released in November of the same year.
On August 19th, 2021, with the announcement of the next major Call of Duty title, Call of Duty: Vanguard developed by Sledgehammer Games, Treyarch confirmed that they were developing the Zombies mode, serving as a prequel of the events featured in the Dark Aether story in Call of Duty: Black Ops Cold War.  
Games developed for the Call of Duty series
Assisted in development
Ported games to different consoles
- Mark Lamia - Chairman
- Dan Bunting - Co-Studio Head
- Mark Gordon - Co-Studio Head
- David Vonderhaar - Studio Designer Director
- Craig Houston - Lead Writer
- Brian Tuey - Audio Director and Composer
- Scott Eckert - Sound Designer/Audio Engineer
- Kevin Sherwood - Sound Designer and Composer
- Neil Masiclat - Lighting Artist
- Adam Alcini - Graphics Engineer
- Jason Blundell - Co-Studio Head, Game Director (Zombies, Campaign)
- Jimmy Zielinski - Creative/Design Director, Zombies
- Jesse Synder - Designer, Creator of Zombies
- Reza Elghazi - Producer, Zombies
- Elena Siegman - Singer/additional voice
- Josh Olin - Community Manager
- Jason McCord - Designer
- Eric Pierce - Contracted TD
- Jeremy Luyties - Design Director
- Mike Denny - Designer
- Jeff Zaring - Designer
- Sean Slayback - Designer
- Zach Volker - Animator
- Gary Spinrad - Senior Sound Designer
- Jason Schoonover - Designer
- Much like Infinity Ward, Treyarch makes references to their company name many times throughout their games, often with the word "3ARC", or "III ARC".
- Treyarch's logo is available as an Emblem in Call of Duty: Modern Warfare 3, unlocked by getting a Final Killcam with a Stealth Bomber.
- Treyarch employees often use the clan tag "3arc" in the multiplayer modes of Call of Duty.
- All the bots in Black Ops series use "3arc" as their clan tag. As well as them all having the names of Treyarch employees.
- If someone tries to change their clan tag to "3arc" and they are not a Treyarch employee, it will not work.