History of the Ruhr and steel industries have declined drastically History of the Ruhr The actual boundaries of the Ruhr vary slightly depending on the source, but a good working definition is to define the Lippe and Ruhr as its northern and southern boundaries respectively, the Rhine as its western boundary, and the town of Hamm as the eastern limit. In the Middle Ages, local power was vested primarily in the counts ("Grafen") of Berg, Mark and Cleves. The left bank of the Rhine was held by the Archbishop of Cologne. The Hellweg was an important trade route crossing the region from Duisburg to
International Authority for the Ruhr International Authority for the Ruhr The International Authority for the Ruhr (IAR) was an international body established in 1949 by the Allied powers to control the coal and steel industry of the Ruhr Area in West Germany. Its seat had been in Düsseldorf. It was agreed at meetings in London on 20 April and 2 June 1949 by the United States of America, the United Kingdom, France and the Benelux countries. The London agreement was signed on 28 April of that year. It was abolished by the Treaty of Paris in 1951, which moved its activities to the European Coal