The game-service's story is coming to an end.
The developers of Warbands: Bushido recently announced that they have decided to shut down the servers:
[...] monetization was recently disabled in the game. Many guessed what this was connected with, and yes, after almost 10 years we will still have to stop the game servers. Thank you all for playing for so many years. It's nice to know that so many players are still fighting in Warbands, despite the fact that we haven't released updates for a long time.
The project was positioned as a "real tabletop turn-based wargame with cards, miniatures, dice."
The Warbands: Bushido page on Valve is available at the following link. The game can be added to the library for free, and Steam trading cards are available for it.