During the ColdWar of the 20th Cenrury the east part of Berlin was the capital of EastGermany, while the western part of the city, in spite of being geographically divided from WestGermany?, continued to belong to WestGermany?. In 1962 the BerlinWall? was built, dividing the city into WestBerlin? and EastBerlin?. This was undertaken by the East German government for economic and political reasons. According to most Westerners, the reason for it was to prevent East Germans from immigrating to the West. So, up to 1999, the Capital of WestGermany? was a small town in NordrheinWestfalen? called BonN?.
After the breakdown of CommunIsm in Europe the city, like the country, was united and soon became capital of all of Germany once again.
Kennedy gave a speech about the BerlinWall? in which he said, with a bad accent, "Ich bin ein Berliner"--something Germans found hilarious, since it meant he's a kind of doughnut.