It is post civil war (March of 1876), and president Grant sits in the White House. The west is still being settled and their are disputes still with many countries. All of contemporary history applies up to this point.
The Wyoming Territory (est. 1868) is still largely unexplored. Currently, it is not a state, but many things are happening in the last decade – railroad expansion, womens rights, native reservation creation… but in the midst of it all, some strange things have been happening in the past year, starting in January of 1875. Prospectors have been vanishing. A small copper mining camp had it entire population vanish in September of 1875. In December, in the freezing cold, tragedy strikes the “20 Mile” silver mine used to run constant – and now no miners meet the railroad engineers and a ghost train came back to town once – no driver, no stoker… no fire burning to fuel it even. In January of 1876 the most notorious and vicious killer ever jailed in the territory, Leadman Jacks, has escaped from the penitentiary and is carving a reign of murder that lead right to the 20 Mile mine.
The territory council has sent several men to investigate. Even the legendary Pinkertons have been brought in to find a man named William Landers Jr., son of a coal man Bill Landers on the east coast. His son was traveling out to 20 Mile in late December to see about buying the mine. Three agents were sent in late January. They were never heard from again. Terror is spreading and folks are starting to leave the territory. The council has sent word to Washington to send its best or risk the entire Wyoming lands losing stability and becoming parceled by local politics – something the federal government does not want to see.