In Berlin, the Huguenots created two new neighbourhoods: Dorotheenstadt and Friedrichstadt. By 1700, one-fifth of the city's population was French speaking. The Berlin Huguenots preserved the French language in their church services for nearly a century. They ultimately decided to switch to German in protest against the occupation of Prussia by Napoleon in 1806-07. Many of their descendents rose to positions of prominence. Several congregations were founded, such as those of Fredericia (Denmark), Berlin, Stockholm, Hamburg, Frankfurt, Helsinki, and Emden.