Diablo II is an action role-playing hack-and-slash video game developed by Blizzard North and published by Blizzard Entertainment in 2000 for Microsoft Windows, Classic Mac OS, and OS X. The game, with its dark fantasy and horror themes, was conceptualized and designed by David Brevik and Erich Schaefer, who, with Max Schaefer, acted as project leads on the game. The producers were Matthew Householder and Bill Roper. The game was developed over a three-year period, with a crunch time of a year and a half.

Blizzard Entertainment, Inc. is an American video game developer and publisher based in Irvine, California. A subsidiary of Activision Blizzard, the company was founded in February 1991 as Silicon & Synapse, Inc. by three graduates of the University of California, Los Angeles: Michael Morhaime, Frank Pearce and Allen Adham. The company originally concentrated on the creation of game ports for other studios' games before beginning development of their own software in 1993, with games like Rock n' Roll Racing and The Lost Vikings. In 1993, the company became Chaos Studios, Inc., and then Blizzard Entertainment soon after being acquired by distributor Davidson & Associates early in the following year. Shortly after, Blizzard released Warcraft: Orcs & Humans.