Final answer:
The oil industry in the United States is thought to have started in Pennsylvania with the drilling of the first commercial oil well in Titusville by Edwin L. Drake in 1859.
Step-by-step explanation:
The oil industry in the United States is thought to have started in Pennsylvania. It was here, in Titusville, that the first commercially successful oil well was drilled by Edwin L. Drake in 1859. This event marked a significant turn in the history of the American oil industry, leading to Pennsylvania being a dominant producer of oil, especially the Bradford Field, which at one point produced 77% of the world's oil supply. The commercial production of oil had by the early 20th century spread to other states such as Texas, California, and Ohio, as well as regions outside of the U.S. However, it was the Drake well in Pennsylvania that began the surge of oil industry operations within the United States.