Cölln on the Fischerinsel is first mentioned in a 1237 document, and Berlin, across the Spree in what is now called the Nikolaiviertel, is referenced in a document from 1244.
During the 15th century, his successors established Berlin-Cölln as capital of the margraviate, and subsequent members of the Hohenzollern family ruled in Berlin until 1918, first as electors of Brandenburg, then as kings of Prussia, and eventually as German emperors.
NSDAP rule diminished Berlin's Jewish community from 160,000 (one-third of all Jews in the country) to about 80,000 as a result of emigration between 19.
After World War II and its subsequent occupation by the victorious countries, the city was divided; East Berlin was declared capital of East Germany, while West Berlin became a de facto West German exclave, surrounded by the Berlin Wall (1961–1989) and East German territory.
From 1470, with the new elector Albrecht III Achilles, Berlin-Cölln became the new royal residence.
Since 1618 the Margraviate of Brandenburg had been in personal union with the Duchy of Prussia.
This was a successful attempt to centralise the capital in the very far-flung state, and it was the first time the city began to grow.
In 1709, Berlin merged with the four cities of Cölln, Friedrichswerder, Friedrichstadt and Dorotheenstadt under the name Berlin, "Haupt- und Residenzstadt Berlin".