Answer :
Rivers played a major role in the settlement of the West of the US in that places that contained rivers were much more likely to be settled--due to the fact that it was easier to transport both goods and humans.
The majority of the settlement happened along major rivers, they did this because it was easier to transport goods such as crops and other goods down the rivers.
The river that had a major part in the development and expansion of America was the Mississippi River. People used the keelboat to river trade, later with the steamboat invention in the early nineteen century transformed the river commerce.