I'm currently reading a book about the American Souix chieftain Red Cloud, the book entitled "The Heart of Everything That Is" by Bob Drury and Tom Clavin. In the book they keep speaking about the mountain man Jim Bridger and how fundamentally important and present he was in many of the events which occurred in the American west. My questions are thus,

How truly important was he in these events? Was it simply due to timing or did he truly "get" what was going on? Which side was he truly on, was he on the side of the native tribes or on the American government?

And, a total aside, any recommendations on books about him? He seems like an incredibly fascinating character that no one really knows about.