Knights From the second half of the 13th century to the 15th century, the crusading Teutonic Knights ruled Prussia through their monastic state. As a consequence, German settlement accelerated along the southeastern coast of the Baltic Sea. These areas, centered around Gdańsk (Danzig) and Königsberg, remained one of the largest closed German settlement area outside the Holy Roman Empire. 17th to 19th century settlements Thirty Years' War aftermath When the Thirty Years' War devastated Central Europe, many areas were completely deserted, others suffered severe population drops. These areas were in part resettled by Germans from areas hit less. Some of the deserted villages, however, were not repopulated - that is why the Middle Ages' density of settlements was higher than today's. Poland In the 16th and 17th centuries, settlers from the Netherlands and Friesland, often of Mennonite faith, founded villages in Royal Prussia, along the Vistula River and its tributaries, and in Kujawy, Mazovia and Wielkopolska. The law under which these villages were organized was called the Dutch or Olęder law; such villages were called Holendry or Olędry. The inhabitants of such villages were called Olędrzy, regardless of their ethnicity. In fact, the vast majority of Olęder villages in Poland were settled by ethnic Germans, usually Lutherans, who spoke the Low German dialect called Plautdietsch. Danube Swabians of Hungary and the Balkans With the decline of the Ottoman Empire, German settlers were called into devastated areas of Hungary, by then comprising a larger area than today, in the late 17th century. The Danube Swabians settled in Swabian Turkey and other areas, more settlers were called in even throughout the 18th century, in part to secure Hungary's frontier with the Ottomans. The Banat Swabians and Satu Mare Swabians are examples of Danube Swabian settlers from the 18th century. An influx of Danube Swabians also occurred toward the Adriatic coast in what would later become Yugoslavia. Settlers from Salzkammergut were called into Transylvania to repopulate areas devastated by the wars with the Turks. They became known as Transylvanian Landler. Galicia After the First Partition of Poland the Austrian Empire took control of south Poland, later known as Kingdom of Galicia and Lodomeria. The colonization of the new crown land began afterwards, especially under the rule of Joseph II. Russian Empire Since 1762, Russia called in German settlers. Some settled the Volga area northwest of Kazakhstan and therefore became known as Volga Germans.