“Deadwood” is set in a mining town that was not part of any U.S. state or territory in the post-Civil War years, and thus was literally lawless. Deadwood attracts people looking to get rich after a huge gold strike, as well as those looking to capitalize on the lack of organized law in the town, built on land stolen from the Sioux.
There are a lot of people who enjoyed the show, and with good reason. It was well written and well acted.
The show was canceled in 2006 without a proper ending, but in 2019 HBO aired a 2-hour finale set ten years after the events of the series.