The castles of Szászvár, Márévár and Kantavár were built in the era as residencies of nobles or the Church. The Order of Saint Paul the First Hermit partially stemmed from the hermit communities of the Mecsek, whom the Bishop of Pécs founded a monastery at Jakab-hegy in 1225. The significant Pécsvárad Abbey also controlled substantial areas in the region. Due to the Ottoman occupation of Hungary and the following wars, raids and over-taxation the population growth stagnated, however the everyday and religious life of the locals didn't change much. The region was protected by its remoteness. After the Treaty of Karlowitz, the local nobles invited German settlers to the region. The territories east of Mecsek became a part of the German ethnic island commonly referred to as Swabian Turkey. Significant amounts of black coal were discovered in the 19th century, the strategic resource greatly advanced the industrialization of the region. Mines were opened in Pécs, Szászvár and Komló which were all subsequently connected to the Hungarian economy with railways. In the aftermath of World War I and the collapse of Austria-Hungary, the Kingdom of Serbs, Croats and Slovenes occupied the region, but the Treaty of Trianon eventually left the area in the possession of Hungary. A huge part of the German-speaking population of the area was expelled from Hungary after World War II, although many German communities lingered. The socialist Hungary further developed the coal mines of Pécs and Komló. Uranium was also discovered and mined near Kővágószőlős from the 1950s. The Mecsek Hills were the scene of pitched battles during the Hungarian Revolution in November 1956 between Hungarian units dubbed "the Mecsek Invisibles" and the invading Soviet forces. After the fall of communism in Hungary, the economically unsustainable mines were closed. The Mecsek now serves mostly as a recreational area with moderate forestry activities. Mecsek is divided to two parts: