Friedrichstadt (Danish: Frederiksstad) is a town in the district of Nordfriesland, in Schleswig-Holstein, Germany. It is situated on the river Eider approx. 12 km south of Husum. It was founded in 1621 by Dutch settlers. Duke Friedrich III of Holstein-Gottorp pursued them to invest capital and knowledge in this region in turn for freedom of their Mennonite and Remonstrant religion (see: Arminianism) and opportunities to reclaim fen and marsh land in the vicinity of the town. One of them was Johannes Narssius. Dutch became an official language. By 1630, many Arminians had already returned to the Netherlands. In 1633 Frederick III sent an embassy to Persia with a view to setting up Friedrichstadt as the European terminus. Despite being led by Philip Crusius, jurisconsult, and Otto Bruggemann or Brugman, merchant, the project proved fruitless.