CONSOL Energy Inc. was first introduced and incorporated by an act of the Maryland legislature on March 1860 as Consolidation Coal Company, but was not fully formed until April 19, 1864. Early in CONSOL's history, transportation of coal proved problematic. The coal was originally transferred by wagon, then by flat-bottom riverboats, and later by railroad. The company collaborated with the Baltimore and Ohio Railroad when a large amount of stock was acquired by the railroad. Two years later, the offices moved from New York to Baltimore.
The company faced internal trouble in the late 1800s due to the company-employed miners going on strike. The strike continued for weeks, with order finally restored by the Maryland Militia. The early 1900s also saw change in the company, when it expanded outside of Maryland into Pennsylvania, West Virginia, Minnesota and Wisconsin, and began to ship coal internationally to Japan.
In 1906, the Baltimore and Ohio Railroad sold its shares to a Baltimore syndicate. This was the first attempt by a railroad to relinquish control of the commodities it transported because of investigation by the Interstate Commerce Commission, which examined the relationships between coal-carrying railroads and the companies having mines on their lines. CONSOL continued to prosper in the early 1900s when it expanded into Kentucky and continued to ship coal all over the world during World War I. The company was able to move its offices back to New York in 1921, and by 1925, the company had become the largest commercial producer of bituminous coal in the United States.
The mergers and reorganizations continued when the company restructured its departments in 1927 to increase efficiency. During the early 1930s and the Depression era, the company again had to reorganize and went into receivership after serious financial trouble befell them, but due to their efforts the company was able to emerge from those years on solid footing.
The year 1934 was the company's seventieth anniversary. They owned 300,000 acres of land containing reserves of 1,800,000,000 tons of coal and operated 22 mines in Maryland, Pennsylvania, West Virginia and Kentucky. The years following World War II saw more mergers and the purchasing of other companies. This is also when CONSOL began to develop new breakthroughs in the coal industry.
In 1945, the company merged with Pittsburgh Coal Company and was renamed the Pittsburgh Consolidation Coal Company. One improvement in 1947 was the creation of "Disco," which became a registered trademark of CONSOL. "Disco" was a smokeless solid fuel, and the coal gasification project became a major endeavor of the company. In 1948, the company developed and built a pilot plant for refining tar from a carbonization process.
In 1951, sufficient data became available to prove to CONSOL that it was economical to transport coal by pipeline. In 1956, CONSOL bought the Pocahontas Fuel Company Incorporated, which had reserves and production facilities of low-volatile coal. These fuels were ideal for coking, which was an important ingredient in the manufacture of steel, and a new venture for the coal company. Two years later, the company shortened its name to Consolidation Coal Company.
A major breakthrough for the company occurred in coal pipelining in 1961 with the creation of coal slurry. Coal slurry, a mixture of coal and water, could be pumped for hundreds of miles through a pipeline, distributed by barge, and stored indefinitely in tanks or ponds. This development was hailed as being one of the most important discoveries in fuel transportation and consumption in the past forty years. In 1963, the company contracted with the Office of Coal Research to develop, construct and operate a coal-to-gasoline pilot plant.
The company celebrated 100 years of operation in 1964. Almost 100 billion tons of coal had been mined and CONSOL was still one of the leading producers of coal in the world, with international holdings as well as successful mines located in various states.
In 1966, just two years after the company marked its centennial, Consolidation Coal was acquired by the Continental Oil Company (Conoco). This was part of a general trend whereby U.S. oil companies extended their reach by acquiring coal reserves and large coal producers. In turn, Conoco was acquired by E.I. du Pont de Nemours & Company in 1981. This purchase was motivated by DuPont’s desire to obtain better control of chemical feedstocks in an era of high oil prices. Consolidation Coal was not a major factor in the Conoco acquisition and did not really fit into DuPont’s strategy, especially after coal and oil prices declined. As a result, it was quickly sold off when DuPont was restructured a decade later.
In 1991, a new holding company, CONSOL Energy Inc., was incorporated as a joint venture of DuPont Energy Company and the German energy conglomerate Rheinisch-Westfalisches Elektrizitatswerk A.G., through its wholly owned subsidiaries Rheinbraun A.G. and Rheinbraun U.S.A. GmbH. Consolidation Coal Company became a wholly-owned subsidiary of CONSOL Energy Inc. DuPont eventually sold most of its half interest, so that by 1998, Rheinbraun affiliates owned 94% of CONSOL Energy stock, while DuPont Energy retained only 6%. CONSOL Energy purchased the entire stock of the Rochester & Pittsburgh Coal Company on September 22, 1998. CONSOL Energy stock began trading on the New York Stock Exchange under the symbol “CNX” in 1999, with an initial public offering of more than 20 million shares.