The roots of Oranje-Nassau Groep B.V. (ONG) lie in the Maatschappij tot Exploitatie van Limburgsche Steenkolenmijnen, which secured the 'Oranje-Nassau' coal mining concession in the Dutch province of Limburg in 1893. Oranje-Nassau Mijnen was the largest private mining company in the Netherlands. The last of its four mining operations was closed down in 1974.
During the last decade of the declining coal mining industry, ONG gradually transformed its mining business into an investment company, focusing on companies, property and energy.
The energy division, Oranje-Nassau Energie B.V. (ONE) entered the oil and gas industry in 1967 at the invitation of a group of American and British oil companies to participate in the first round of acreage licensing on the Dutch Continental Shelf. Since its entry into the oil and gas market, ONE has gradually developed into an internationally oriented active investor in the upstream sector.
Following a reassessment of its business strategy during the late 1980’s, ONE shifted its focus from investments in exploration ventures into investing in already proven (producing) oil and gas fields. In the North Sea ONE acquired interests in inter alia, P15/P18, F3-Fb, F2a Hanze, F15 (the Netherlands), Wytch Farm, Gryphon, Waveney, Cook, Janice, Pierce, Elgin Franklin and Buzzard (the United Kingdom). In Africa, ONE acquired assets in Algeria (Issaouane), Congo, Egypt (Geisum), and Tunisia (Ezzaouia and Robbana). Other acquisitions were completed in Spain (Casablanca field) and Yemen. A number of these assets, including the non North Sea positions, were subsequently divested over time.