To me it is pretty much literally an interactive novel or movie.

There is no bright line (nowadays) separating games from interactive movies and there are certainly hybrids around. The problem with good full-immersion games is that they really hard to make, I think the screen and the controls actually get in the way and a good book is able to achieve better immersion because your imagination has more freedom.

Usually, if you want to experience a game just for the story, you can put the difficulty on Easy, one-hit everything and travel the game world. Some very successful games -- like Skyrim -- aren't so much about "winning" as they are about constructing your own experience.

The landscape of games is pretty varied, though. If you want to "realistically" swing your sword you can play the Witcher series; if you want a Medieval-ish open-world sandbox without much pressure to conquer anything you can play the Mount & Blade series; Civilization-style games offer country management without the necessity to conquer everyone else...

everybody teams up in alliances against factions that conquer more than five provinces would do it.

That's Total War Shogun 2 :-)