The Texas Commonwealth is a southern state of the United States of America (or what remains of it), which consists of Texas and Arkansas, it is the main location in Finding Kurisu.
Post Great War
The Texas Commonwealth, like Boston and Washington DC had mostly remained an anarchistic wasteland, with no prominent factions rising up to take power. One of the main reasons for this was the twisters and cyclones, that tore through the region, like angry Gods. A number of tribes existed, scattered along the region, such as the Mourners, a lot of these tribes took to worshipping the tornadoes as Gods and some even believed to control them. It wasn't until the 2200s, when the Brotherhood of Steel arrived did it's makeup begin to change.
The Brotherhood found themselves tracking down some Marissopa Mutants, who had congregated around the region, trying to create a second unity of sorts. Their leader, Attis was fought and killed by a hero remembered only as 'The Initiate.'
After Attis' death and the destruction of his Vault, the only surviving member of the incident (known to the people) was Cain, a ghoul recruit, who was savage enough to prove to be a force to be reckoned with for the Mutants.
The Birth of the Commonwealth
Cain returned to where his journey began, Carbon, a small town that wasn't even featured on most maps, was taken over and renovated by the initiate and those willing to follow him. He was popular, despite his ghastly appearance, due to him saving the town from raiders, just over a year before. His iron-fisted rule was seen as tough but fair and thus, he began conducting the restoration of the town.
The Ghoul quickly found himself being called upon to help nearby towns, it caused him to feel for the people in them as they faced injustice every day but he struggled to come up with a way to expand across the entirety of the biggest continent in the United States, within less than one hundred years.
Cain decided to fund his empire with slavery, a decision that he didn't take easily but one that he knew was necessary. At first it was Raider prisoners, who he used as slaves but then he started to branch out as he took primitive tribals and the destitute for his slave trade.
This seemed to work, allowing him to turn Carbon into the center of a glorious post apocalyptic Empire. If he wanted to, he could rival Caesar's Legion and so, this caught the attention of the Brotherhood of Steel.
Brotherhood Civil War
Though Cain was not fully considered a member of the Brotherhood anymore as he went AWOL years ago, he was a Brotherhood Hero and so, his actions still disgraced them. As such, Elder Woolf, the leader of the Illinois chapter of the Brotherhood of Steel was sent to Arkansas, where she had to clear out Cain's rapidly expanding bases.
The campaign seemed like it would be over quickly. Arkansas was conquered in less than a year as the bases were numerous but thinly spread across the southern regions of the state. However, upon arriving in Texas itself, the situation quickly changed.
It took the best part of five years to even get a foothold into the state and even then they struggled to hold any territory. It wasn't until 2254, when Woolf's people were actually able to take Lindale and hold it comfortably. It was at this point that Cheyenne arrived, with her companion Sulik, looking for his Sister, Kurisu.
Fallout: Brotherhood of Steel