In the 12th century, the Curonians dwelt in the east Baltic region between the Rīga area in the north and Klaipėda in the south. They reached the peak of their economic, political and cultural achievements in the 11th century and the first half of the 12th century. The roots of piracy as a phenomenon have a social character. The most active period of the Curonian Vikings begins in around the mid-tenth century, and lasts until the arrival of the Germans in the 13th century. The well-organised piracy of the Curonians became dangerous to navigation on an important maritime trading route along the east Baltic coast. The Curonians attacked traders’ boats, robbed coastal churches, devastated Danish and Swedish coastal areas, and even stayed for a while. In the times of the Teutonic Order, in periods of diplomatic and military conflict or trading competition, even officials did not avoid robbery at sea. The Palanga coastal population used to plunder shipwrecked boats, and went marauding in coastal waters until the middle of the 18th century.