Hagen is the 39th-largest city in Germany, located in the federal state of North Rhine-Westphalia. It is located on the eastern edge of the Ruhr area, 15 km south of Dortmund, where the rivers Lenne, Volme and Ennepe meet the river Ruhr. As of 31 December 2010 the population was 188,529. The city is home to the FernUniversität Hagen, which is the only state funded distance education university in Germany. Counting more than 67,000 students (March 2010), it is the largest university in Germany. 
Hagen was first mentioned ca. 1200, presumably the name of a farm at the junction of the Volme and the Ennepe. After the conquest of Burg Volmarstein in 1324, Hagen passed to the County of Mark. In 1614 it was awarded to the Margraviate of Brandenburg according to the Treaty of Xanten. In 1701 it became part of the Kingdom of Prussia.
The growth of the city began in the 19th century with the mining of coal and the production of steel in the Ruhr Area. It was the scene of fighting during the Ruhr Uprising, 13 March - 2 April 1920 and has a monument to the Ruhr Red Army.
In 1928 Hagen developed into a city of more than 100,000 inhabitants.
On the night of 1 October 1943, 243 Lancasters and 8 Mosquitos from the Royal Air Force's Bomber Command attacked the city. According to the Bomber Command Campaign Diary, "This raid was a complete success achieved on a completely cloud-covered target of small size, with only a moderate bomber effort and at trifling cost." Severe damage was caused.