The Wasteland stretches from one horizon to the other, and very few people can say that they have walked it all. If a traveler sets out from the Boneyard on the West Coast and walks towards the rising sun in the East, it would take months before they reached the other ocean. It used to take a lot less time. Some of the old flight records at airfields say that people would fly back and forth across the entire country in an afternoon. Not many of those flying vehicles made it through the Great War intact, and the people who use them aren't likely to take on passengers. The roads used to be smoother, and people built a steel bridge over every little river that got in their way. Even when folks didn't have the time to fly from one city to the next, they could still communicate over great distances. At the time of the Great War this was done through wireless satellite transmissions, but even four hundred years ago people could communicate all the way across the country with a network of wires that were strung up on poles that lined the highways and railroad tracks. Some of those poles are still standing today, but the wires don't go anywhere anymore. So today, if you want to know what's happening on the other side of the horizon, there's only one way to find out. Go see for yourself.
Lots of people go their whole lives without traveling more than a few days walk from the village where they were born. But for organizations like the Brotherhood of Steel, long distance travel and communication are on the front burner.
The Brotherhood of Steel has taken it upon themselves to preserve the technology of the old world. There's plenty of old gizmos and gadgets out in New California, but the truth is, the capital of this nation used to be out on the East Coast. A few decades ago, in 2254, the Brotherhood dispatched a military contingent to the east, to recover advanced technologies from cities and bases dotting the Eastern Seabord. The Brotherhood sent teams East before, to Chicago, and some folks say they planned a mission to Boston, but the Capital Expedition was one of the most ambitious projects the Brotherhood had ever undertaken.
A promising Paladin named Owyn Lyons was chosen to lead a force that would learn what had become of Washington and the surrounding area. After months on the road, the first reports from Lyons weren't promising. They passed through a hellhole that was appropriately named the Pitt. This pit of human misery fared worse than most after the Great War. "Pittsburg" is what they used to call it back then. Lyons led a Scourge of the city, killing any who fought back. Something was recovered that day, but only the Elder knows what it was. When the Brotherhood left the desolate city behind, the caravan carried twenty unmutated children saved by the troops.
This was the first of many unconventional moves from Paladin Lyons; he not only rescued those children, but he defied tradition and made them Initiates in the Brotherhood. Most of the people in the Brotherhood are born into it. Most of the people in the Brotherhood are born into it, descended from their ancestors that helped form the order two centuries earlier. Taking in an outsider is extremely rare for any Brotherhood chapter, but to recruit a group of children descended from irradiated scavengers and slaves? To some that made Lyons a hero. To others a pragmatic leader who needed the extra hands. And a few people saw him as mongrel-loving traitor to the Brotherhood.
The Capital Expedition didn't stop with the Pitt, they pressed on into a region called Maryland, fighting raiders and slavers wherever they found them until they came to what was once the capital city of this land - and what they found didn't fill them with hope.
Aside from slavers, raiders, and feral ghouls, there were also some of the biggest super mutants they'd ever seen. All of them full of rage and ready to attack on site. This was nearly a hundred years after The Master's Super Mutant army had been scattered, and Washington had the worst infestation of them Lyons and his soldiers had seen.
The disorganized band of humans were no match for the mutants. Out East, people live in pathetic little villages built in the ruins of highway onramps, the basements of pre-war monuments, and even some crazy folks who built a town out of the husk of a bomber plane - complete with a nuclear bomb right in the middle of town. There was no organization that could stand against the mutants.