Buckle up, this is a long post (~2800 words). Will probably go back and do some editing later.
In 1997, Interplay Entertainment’s subsidiary Black Isles
released a small videogame called Fallout:
A Post Nuclear Role Playing Game, and released a follow-up the next year in
Fallout 2. Black Isles hasn’t existed
for years, not since Interplay’s financial troubles (which also forced the
company to sell the rights to the Fallout
series in 2006 to Bethesda Softworks), but the core membership of Black
Isles (including Fallout 2 directors
Tim Cain and Chris Avellone) founded a new development company called Obsidian,
which you may be familiar with.
In 2008, Bethesda published Fallout 3, transforming the originally grid- and turn-based combat
isometric into a 3D, first-person camera format much like Bethesda’s other
flagship series, The Elder Scrolls. In
2010, presumably because Bethesda was busy developing Skyrim, Obsidian released a gaiden game called Fallout: New Vegas, set in the Mojave Wasteland (where parts of Fallout 1 and 2 take place), featuring many elements from Black Isles’ planned Fallout: Van Buren as well as a number
of factions from the original isometric games.