Coal and wood are two sources which had been used extensively since the 18th century. when steel was commercialized heavily using the Bessemer Proces later at the 19th century. At this time, petroleum became the major energy source of energy and was even used extensilvely in other processes as converting petroleum to fuels.
Answer:
Because it would be easier to fetch water and also because lands near the rivers are fertile to grow crops
They mostly settled in the south eastern part of america.