Disclaimer:
This RP is going to be based on the fallout series. Stuff going on in fallout 1,2,3,NV, and presumably 4(though what we know about it is lacking) ,are considered cannon. If you have doubts about something please ask, the fallout wiki is also rather useful. also, check out https://www.youtube.com/watch?v=nvqm_pPD-aQ&list=PL7pGJQV-jlzD17YNNbt103xp0PkkUCoPU . Shoddycast did a lot of nice vids on it too.

War, War never changes

The Brotherhood of steel high elders have feared one thing above all else ever since the hero from vault 13 put down a mangled mess of flesh and machine. They have feared this one thing above all else. They have feared it more than the enclave, more than the speratic factions gaining power, more than an entire settlement of humans being armed with fat boys with an unending supply of mini nukes. They've feared the resurrection of the Master above all else... thankfully that never occurred... or so they hoped.

Unbeknownst to the Brotherhood after decades of time, A mangled mass of flesh and machine had received a successor, and not some delusional night kin out in the Mohave. This was a true successor, one who picked up right where the master left off. This.... This new Successor was known only as "The Overlord", and his actions have been spreading across the Northwest Commonwealth. Even though the brotherhood was still reeling from the conflict with the new California republic The high elder sent a contingent up north to investigate, See if the stories were true, and hopefully put an end to the trouble, one way or another.

But this isn't the story of the brotherhood. This is the story of the Marshals... the Lawmen up north in the old commonwealth and their hunt to bring down whatever is terrorizing the great west.