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Is Skyrim's story related to the previous Elder Scrolls games?
Are Oblivion and Skyrim related?
If they are, should I play Oblivion before playing Skyrim?
12 Answers
Both games contain events from a world called Tamriel, and in fact Skyrim contains the entire (unplayable) map area of Morrowind (Elder Scrolls 3) and Cyrodiil (from Oblivion). However, the events of the Elder Scrolls series stories are not interrelated and they generally have very few references to one another.
Many game elements and concepts carry over between the modern Elder Scrolls games, with various guilds, skills, enemies, items, and races that are shared between them. To make an extremely geeky analogy, you could ask "Should I watch the original Star Trek series before watching The Next Generation?" Some people might feel that the only way to get every reference is to watch them in order, but Skyrim is certainly set up so that you can jump into the game with no prior knowledge of the Elder Scrolls series.
If you enjoy Skyrim though, you might want to pick up Oblivion or even perhaps Morrowind. They're both quality games that will provide many hours of enjoyment, should you finish Skyrim and decide you want more.
1They aren't related. There are minor references to Oblivion in some places, but for the most part Tamriel wants to forget that Oblivion ever happened.
As to whether you should play it, I think most people agree that Oblivion is significantly inferior to Skyrim. Personally, I never finished Oblivion because I couldn't stick with it (though, I did mostly enjoy what I played of it), but I finished Skyrim within a week of release and putting in a 90+ hour effort doing it. Loved it.