22 Developers and a $1.5 Million Bet: The Story of Call of Duty
A team that walked out of a rival series built a World War II shooter in 2003. Twenty-three years and more than 500 million copies later, Call of Duty has a new game every year and a $68.7 billion owner.
In May 2002, three developers, Grant Collier, Jason West and Vince Zampella, set up a new studio in California. All 22 of its first members came from the team that had just made Medal of Honor: Allied Assault for Electronic Arts, the biggest war shooter of its day. They called themselves Infinity Ward, and Activision paid $1.5 million for a 30% stake to fund their first game.
That game, Call of Duty, launched on October 29, 2003. The series has since sold more than 500 million copies, the best-selling first-person shooter series according to Guinness World Records, and released a main game every year since 2005. Its newest, Modern Warfare 4, arrived on October 23, 2026. Here is how it got so big.
World War II, but with friends
The first Call of Duty set itself apart from Medal of Honor by putting you inside a squad. Instead of a lone hero, you fought alongside soldiers who moved, shouted and died around you, across American, British and Soviet campaigns.
Call of Duty 2 came out on Windows on October 25, 2005 and weeks later on Microsoft's new Xbox 360, as one of the console's launch games. To keep up a faster pace, Activision brought in a second studio: Treyarch made Call of Duty 3 (2006), the first main entry not developed by Infinity Ward. The alternating-studio model that still runs the series was born.
2007: Modern Warfare changes everything
The real breakthrough came on November 7, 2007. Call of Duty 4: Modern Warfare left World War II behind for a modern setting, and its tight multiplayer, with unlockable perks and rewards for kill streaks, became the template for online shooters for a decade. It had sold over 13 million copies by May 2009.
Treyarch answered in 2008 with World at War, which introduced a cooperative bonus mode called Nazi Zombies. It became so popular that Zombies grew into a pillar of the series. Then Modern Warfare 2 (November 10, 2009) and Black Ops (November 9, 2010), the first Cold War entry, turned each November launch into one of the biggest days in entertainment.
A third studio, Sledgehammer Games, joined to co-develop Modern Warfare 3 (2011) and later led Advanced Warfare (2014), WWII (2017), Vanguard (2021) and Modern Warfare III (2023).
Free to play, phones and a new owner
The series' next big shift was going free. Call of Duty: Mobile, made by Tencent's TiMi Studios, launched worldwide on October 1, 2019 and passed 35 million downloads in its first three days. Warzone, a free battle royale, followed on March 10, 2020 and reached more than 50 million players in its first month.
Then came the biggest deal in gaming history. Microsoft announced it would buy Activision Blizzard on January 18, 2022 for $68.7 billion and completed the deal on October 13, 2023. As part of winning regulatory approval, Microsoft committed to a ten-year deal to bring Call of Duty to Nintendo platforms. In 2026, that promise arrived: Modern Warfare 4 launched on PC, PS5, Xbox Series X|S and Nintendo Switch 2.
Why it matters
Call of Duty did not invent the military shooter, but it industrialised it. Rotating studios, yearly releases and a multiplayer system built around progression changed how blockbuster games are made and sold.
WGC's take: the annual schedule has produced great years and tired ones, and the 2025-2026 shooter battle with Battlefield 6 showed the series is no longer untouchable. Read our shooter showdown for how that fight is going.
What to play next: Modern Warfare 4 is the newest, and Call of Duty's free-to-play modes are the cheapest way in. For history, the Call of Duty 4 campaign remains one of the most influential shooter stories ever made.