The Brotherhood of Steel is a quasi-religious technological organization operating across the ruins of post-war North America, with its roots stemming from the American military and the government-sponsored scientific community from Fialer Earth. The Brotherhood is mostly composed of the descendants of those military officers, soldiers, and scientists, but aside from some outsiders among their ranks, the Brotherhood is as close to pure-strain humanity (prime normal) that may be found outside of a Vault or the Enclave. The ranks of the Brotherhood of Steel are generally recognized as being composed of the best and the brightest remaining to humanity, which means the BoS is a relatively small organization, at least compared to the New California Republic. They make up for this with their intimidating arsenal of pre-and-post-Great War technology: they have laser and plasma weapons, power armour, surgical cybernetic enhancements, combat implants, and Brotherhood Paladins have the ability to erase an entire city from the map without a scratch. The vast majority of BoS members are born into the Brotherhood - they very rarely accept outsiders into their ranks. While not an official policy, many members believe that in order to survive, all members are obligated to procreate. This results in a lack of tolerance for same-sex relationships, at least when the proponents of the aforementioned stance are concerned. Those born in the Brotherhood that want to be neither Scribes, Knights nor Paladins are free to leave - the Brotherhood does not believe in forcing anyone to serve them against their will. Although, members who decide to leave the Brotherhood will face the punishment of death for sharing any medical or scientific knowledge they have acquired with any outside faction. But, following the Combine's invasion and occupation of their home world, the Brotherhood have sense became a major faction on Fialer Earth that fights the Combines and have joined the Alliance of Nations to fight the occupying Axis.