There is a great Viking inspired game being developed called The Banner Saga. It will be DRM free and with your direct input you can help make sure this is released for linux operating systems (like Ubuntu) as well.
The Banner Saga is a role-playing game merged with turn-based strategy, wrapped into an adventure mini-series about vikings.
Travel through stunning landscapes straight out of an animated film. Battle painstakingly hand-animated foes in strategic, turn-based combat harkening back to the classic "Tactics" days of gaming. Make decisions with consequences in conversations with people you'll truly care about.
And throughout the whole thing record the history of your people on your banner where it will be remembered, because soon there might not be anything left.
The Banner Saga is a mature game aimed at gamers who appreciate art, story and strategy.
DID WE MENTION ONLINE MULTIPLAYER?
You can learn more about the game and even donate here: