When was the first Fallout game released?

Context: Fallout is a series of post-apocalyptic role-playing video games—and later action role-playing games—created by Interplay Entertainment. The series is set during the 21st, 22nd and 23rd centuries, and its atompunk retrofuturistic setting and art work are influenced by the post-war culture of 1950s United States, with its combination of hope for the promises of technology and the lurking fear of nuclear annihilation. A forerunner of Fallout is Wasteland, a 1988 game developed by Interplay Productions to which the series is regarded as a spiritual successor.

The series' first title, Fallout, was developed by Black Isle Studios and released in 1997, and its sequel, Fallout 2, the following year. With the tactical role-playing game Fallout Tactics: Brotherhood of Steel, development was handed to Micro Forté and 14 Degrees East. In 2004, Interplay closed Black Isle Studios, and continued to produce Fallout: Brotherhood of Steel, an action game with role-playing elements for the PlayStation 2 and Xbox, without Black Isle Studios. Fallout 3, the third entry in the main series, was released in 2008 by Bethesda Softworks, and was followed by Fallout: New Vegas, developed by Obsidian Entertainment. Fallout 4 was released in 2015, and Fallout 76 released on November 14, 2018.

Bethesda Softworks owns the rights to the Fallout intellectual property. After acquiring it, Bethesda licensed the rights to make a massively multiplayer online role-playing game version of Fallout to Interplay. The MMORPG got as far as beta stage under Interplay, but a lengthy legal dispute between Bethesda Softworks and Interplay halted the development of the game and led to its eventual cancellation, as Bethesda claimed in court that Interplay had not met the terms and conditions of the licensing contract. The case was settled in early 2012.

Origins
The ideas of the Fallout series began with Interplay Productions' Wasteland, released in 1988. At that time, Interplay was not a publisher and used Electronic Arts for distribution of the game. According to Interplay's founder, Brian Fargo, they wanted to explore a post-apocalyptic setting and created Wasteland for that. Sometime after release, Interplay decided to shift focus and become a publisher while still developing games. Fargo wanted to continue to use the Wasteland intellectual property but could not negotiate the rights back from Electronic Arts. Still wanting to do something in a post-apocalyptic setting, Fargo and his team decided to make a new setting and game. They determined what aspects of Wasteland were positives and wrote and developed a new game around them. The result was the first Fallout games, which released nearly ten years after Wasteland.

Answer: Fallout (1997)
Released in October 1997, Fallout takes place in a post-apocalyptic Southern California, beginning in the year 2161. The protagonist, referred to as the Vault Dweller, is tasked with recovering a water chip in the Wasteland to replace the broken one in their underground shelter home, Vault 13. Afterwards, the Vault Dweller must thwart the plans of a group of mutants, led by a grotesque entity named the Master. Fallout was originally intended to run under the GURPS role-playing game system. However, a disagreement with the creator of GURPS, Steve Jackson, over the game's violent content required Black Isle Studios to develop the new SPECIAL system. Fallout's atmosphere and artwork are reminiscent of post-World War II United States during the Cold War era and the fear that the country was headed for nuclear war in the real world.