Why did native americans fight for land and water

I am sort of confuse becouse this is phrased as one question (at first i thought you where talking about the recent fight about not putting in a pipeline but i relized you said why DID)

So i will split it into 2 Native americans fought for land becouse for one they needed a place to live and second they belived the great spirit wanted them to live where they did

They fought for water to live/drink