id Software | Code Like It's 198x

In 1990 a group of programmers at Softdisk, a software subscription company in Shreveport, Louisiana, spent a weekend making Super Mario Bros. 3 scroll smoothly on an IBM PC. PCs were not supposed to do that. They sent the demonstration to Nintendo, which was impressed but wanted Mario kept on its own machines. So they used the trick for a game of their own, Commander Keen, and in February 1991 four of them left to form id Software. Wolfenstein 3D made it, in Computer Gaming World’s words, the “king of the action-game hill”, and Doom carried its games onto office networks.

id’s story is mostly told through two people: John Carmack, who wrote the engines, and John Romero, who designed levels and wrote tools. But it was a small team throughout, and the way it sold its games mattered as much as the code.

Fast facts

Founded: 1 February 1991, in Shreveport, Louisiana.
Founders: John Carmack, John Romero, Adrian Carmack (no relation) and Tom Hall.
Moved: to Madison, Wisconsin, in September 1991; to Mesquite, Texas, on 1 April 1992; to Richardson, Texas, in 2011.
Key games: Commander Keen (1990–91), Wolfenstein 3D (1992), Doom (1993), Doom II (1994), Quake (1996), Quake II (1997), Quake III Arena (1999), Doom 3 (2004), Doom (2016).
Owners: independent until ZeniMax Media, the parent of Bethesda Softworks, bought it in June 2009; Microsoft bought ZeniMax in 2021.
Source code: released for its engines from Wolfenstein 3D onwards, including Doom in 1997 and Quake in 1999.

From Softdisk

Softdisk’s games division, Gamer’s Edge, sold a subscription disk of new games for IBM PC compatibles; by December 1991 Softdisk advertised it at $10 a month, “every month”. Romero, the Carmacks and Hall worked there. Calling themselves Ideas from the Deep, they used Carmack’s smooth-scrolling technique, “adaptive tile refresh”, for Commander Keen in Invasion of the Vorticons, which came out in December 1990. It was published by Apogee, Scott Miller’s shareware company: the first episode was free to copy, and players paid for the rest.

The four left Softdisk on 1 February 1991 and called their company id. Softdisk had not been happy that the Keen work was done on its computers, and id agreed to keep supplying Gamer’s Edge with games, at $5,000 each, until the end of January 1992. Those contract games became id’s laboratory. Hovertank One (May 1991) put the player inside a tank in a maze of flat-coloured walls. Catacomb 3-D (November 1991) added textures to the walls and put the player in a battle mage’s shoes. Tom Hall later wrote that each of them “could be considered the first FPS”. Meanwhile Commander Keen: Goodbye, Galaxy! reached Apogee’s customers on 15 December 1991.

Wolfenstein and Doom

In September 1991 the team moved to Madison, Wisconsin, where Hall and Jason Blochowiak had been at school, and in January 1992 started a game based on the Apple II classic Castle Wolfenstein. Wolfenstein 3D took four months and went out through Apogee on 5 May 1992, its first episode shareware. Tired of the Wisconsin winter, id had moved to Mesquite, a suburb of Dallas, on 1 April. “Commander Keen made good money,” Hall recalled. “Wolfenstein 3D made TEN TIMES that.” GT Interactive later sold it in a box.

With Doom id published for itself. It gave away the first episode, took orders on 1-800-ID-GAMES and let shops sell the free episode and keep the money. Computer Gaming World named Jay Wilbur as id’s chief executive. When a Doom craze broke out on company networks, he had a line ready for the magazine: “If you haven’t played multiplayer DOOM, you haven’t played DOOM!”

The team comes apart

Success did not keep the founders together. Hall left during Doom, in August 1993, over creative differences, and went to Apogee. Romero left in 1996, after Quake, and by January 1997 Computer Gaming World was reporting “John Romero’s departure and Jay Wilbur’s retirement” in the same sentence. Romero and Hall set up Ion Storm together in Dallas. In November 1996 the magazine named Carmack tenth among the industry’s most influential people: without his “programming tricks and gaming instincts”, it said, “it is questionable whether Wolfenstein 3D, Doom and Quake would have been made”.

id brought its fans to Texas: QuakeCon, a players’ gathering near its offices from August 1996, became an annual event that id paid for and ran.

Engines for hire, code for everyone

id sold its technology to other studios. Raven Software, in Wisconsin, used the Quake engine for Hexen II; Ritual Entertainment announced Sin on it and moved to the Quake II engine before release; and Valve built Half-Life on an enhanced version. Computer Gaming World observed that “even games from other companies such as Dark Forces and Duke Nukem 3D owe much to the basic design of Carmack’s games”. The engine lineage is described under id Tech.

id made a habit of publishing an engine’s source code once it was a few years old. Doom’s code came out on 23 December 1997, “for your non-profit use” in Carmack’s words, and was relicensed under the GNU General Public License in 1999. Quake’s followed under the GPL on 21 December 1999, then Quake II in 2001, Quake III Arena in 2005 and Doom 3 in 2011. Fabien Sanglard, who has written books on both engines, notes that from 1993 to 2012 id released the code of every game it produced. The Doom code alone produced hundreds of “source ports”, from Boom and ZDoom to Chocolate Doom, several still developed today.

Under new owners

Doom 3, in August 2004, took the series towards slow-paced horror and sold more than 3.5 million copies by 2007. In June 2009 ZeniMax Media, the owner of Bethesda Softworks, bought id. Carmack became chief technology officer of Oculus VR in August 2013 and left id that November; Wireframe noted that most of “the big names” had gone by then, and that id “fell into relative obscurity” while its new Doom took years to appear.

It returned with Doom in 2016, praised for going back to speed, and Doom Eternal in 2020. In September 2020 Microsoft agreed to buy ZeniMax for $7.5 billion, and the purchase was completed in March 2021. Since then id has released an enhanced edition of Quake (2021), made with Nightdive Studios, Doom + Doom II (2024) and Doom: The Dark Ages (2025). QuakeCon is still held every August near Dallas.

Sources

Fabien Sanglard, Game Engine Black Book: Wolfenstein 3D (2017): Tom Hall’s foreword (Hovertank and Catacomb 3-D “could be considered the first FPS”, the choice of Castle Wolfenstein, “Wolfenstein 3D made TEN TIMES that”); chapter 1 (release on 5 May 1992); chapter 3 (Softdisk and Gamer’s Edge, the Super Mario Bros. 3 demonstration and Romero’s account of Nintendo’s reply, the founding on 1 February 1991 and its founders, the Keen, Softdisk and 1991 release dates, the Softdisk contract to 31 January 1992, the move to Madison, the four-month development, distribution through Apogee and GT Interactive’s boxed edition).
Fabien Sanglard, Game Engine Black Book: DOOM (2018): chapter 4 (the Doom team, Tom Hall’s departure in August 1993, the move to Mesquite on 1 April 1992, distribution); section 5.1 and appendix E (the Doom source release, 23 December 1997, and the footnote that id released the code of all its games from 1993 to 2012); the epilogue (Doom 3 sales, Doom (2016), the source ports).
“Developer Profile: id Software”, Wireframe issue 16, June 2019, pp. 50–53: Softdisk and Gamer’s Edge, Ideas from the Deep, the Softdisk arrangement at $5,000 a game, Apogee and Scott Miller, Romero leaving in 1996 and Carmack in 2013, id’s “relative obscurity”, QuakeCon’s first event outside the United States.
Bryan Walker, Computer Gaming World issue 116, March 1994, pp. 37–39: Doom review (id “king of the action-game hill”; publisher id Software, 1-800-ID-GAMES; Jay Wilbur as CEO and his quotation).
Computer Gaming World issue 148, November 1996: “The Most Influential Industry Leaders” (Carmack tenth, and the quotations).
Computer Gaming World issue 150, January 1997: Romero’s departure and Wilbur’s retirement; Ion Storm with Tom Hall.
Computer Gaming World issue 155, June 1997 (Hexen II on the Quake engine) and issue 158, September 1997 (Half-Life and Sin on the enhanced Quake engine) and issue 161, December 1997 (Sin moving to the Quake II engine).
Wireframe issue 43, September 2020, p. 19: Microsoft’s $7.5 billion agreement to buy ZeniMax Media.
id Software, DOOM and Quake repositories on GitHub (web, secondary): Carmack’s 1997 note, and the GPL licences. https://github.com/id-Software
“id Software”, Wikipedia (web, secondary): the move to Richardson in 2011, ZeniMax’s purchase on 24 June 2009, Carmack joining Oculus VR in August 2013 and leaving id in November 2013, completion of Microsoft’s purchase in March 2021, the later source code releases and the practice of releasing an engine’s code when it was about five years old, and the games from 2016 to 2025. https://en.wikipedia.org/wiki/Id_Software
“Doom engine” and “Quake engine”, Wikipedia (web, secondary): the Doom relicensing under the GPL on 3 October 1999 and the Quake release on 21 December 1999. https://en.wikipedia.org/wiki/Doom_engine and https://en.wikipedia.org/wiki/Quake_engine
Softdisk advertisement for Gamer’s Edge, Computer Gaming World issue 89, December 1991: “Gamer’s monthly software subscription”, $10 a month, for IBM compatibles.