The Pennsylvania Rock Oil Company was established in the mid-19th century, primarily known for its role in the early oil industry. It was one of the first companies to extract and refine petroleum in the United States, contributing to the growth of the oil industry and the development of oil drilling techniques. The company played a significant part in the Oil Boom of the 1850s, particularly in Titusville, Pennsylvania, where the first commercial oil well was drilled. Its operations helped pave the way for future advancements in energy production and the widespread use of oil in various industries.