Berlin, situated at the river Spree, was created out of two towns, Berlin and Cölln. In 1237, under the reign of counts Johann I. and Otto III., both places received the right to be called 'town'. In 1442 Friedrich II., also called: the firm one, member of the family 'Hohenzollern' build a castle. With that the town lost its independence. From 1486 on, Berlin was constant capital for the counts of Brandenburg. The number of inhabitants decreased dramatically down to 6000 while the '30-year-war'. Under the great count who called the 'Hugenotten' into the city of Berlin, it experienced a great boom. Friedrich Wilhelm I. and Friedrich, the Great, made Berlin into the leading industrial city of Preußen. Therefore, in 1786, the town

counted 147000 people. In 1810, the University of Berlin opened up. In 1861, after the Independence wars the number of inhabitants increased up to half a million. After Berlin became the capital of whole Germany under the reign of the emperor Wilhelm I., in 1871, it soon developed into a city with more than a million people. After World War One, the family of the 'Hohenzollern' had to give up their power. In 1920, through the incorporations of towns around Berlin - 'Great Berlin' was created. In 1939, the city already counted 4,3 million inhabitants. With the end of the Third Reich, in 1945, Berlin was divided into 4 part. In 1961, the Wall was build.