In 1388, Count von Mark joined forces with the Archbishop of Cologne and issued declarations of a feud against the town.
Following a major siege lasting 18 months, peace negotiations took place and Dortmund emerged victorious.
The town expanded into a city, with the population rising from 57,742 in 1875 to 379,950 in 1905.
The code word Dortmund was radioed to initiate the 1941 Operation Barbarossa campaign against the Soviet Union.
The Allied ground advance into Germany reached Dortmund in April 1945.
After the Thirty Years' War the city was destroyed and decreased in significance until the onset of industrialization.
The city then became one of Germany's most important coal, steel and beer centres.
This bombing raids with more than 1,110 aircraft was a record to a single target in World war II.