The French settled along water sources because

Answer 1

A number of reasons, but probably the largest one is transport. In unsettled territory (i.e., most of the country, at the time) it was very difficult to move people and goods when there were no roads in place. Rivers were ideal for that--boats could bring in men and material to build settlements, and then take trade goods back downriver to send back to France (or to other trading ports along the way). And the portions of the US that had navigable rivers and streams was quite high in colonial times. The Mississippi alone went all the way from the Gulf of Mexico to Minnesota.