a federal state. The following districts are wholly or partially part of Upper Swabia: Alb-Donau Biberach Bodenseekreis (Lake Constance) Ravensburg Reutlingen Sigmaringen Ulm History Upper Swabia has been populated at least since the Neolithic age. Archaeological evidence confirming this was discovered around the Federsee, a lake near Bad Buchau. Until around the year 260 CE, the region that was to become Upper Swabia, was part of the Roman province of Raetia, after which the Alamanni invaded the Agri Decumates and settling there. During the Merovingian period, Upper Swabia came under the rule of the Frankish kings. It was part of the Duchy of the Alamanni. During the same period, the Christianization of the region began. During the Carolingian, Ottonian and Salian period, Upper Swabia was part of the Duchy of Swabia. From the High Middle Ages onwards, Upper Swabia became fragmented into a large number of small independent political units: Free Imperial Cities, principalities, counties, seigneuries, Imperial Abbeys and other clerical territories. During the German Peasants' War of 1524–1525, Upper Swabia was a centre of the revolt. The peasants formed three armed groups, called Haufen (or Haufe): the Allgäuer Haufen, active in the Allgäu and eastern Upper Swabia, the Seehaufen, centred on the region north of Lake Constance, and the Baltringer Haufen, named after the village of Baltringen, a few kilometres south of Laupheim in northern Upper Swabia. During the revolt, numerous castles and monasteries in Upper Swabia were destroyed by the peasants. By July 1525, however, the rising had been utterly suppressed in Upper Swabia, with countless peasants losing their lives either due to battles or due to punitive measures inflicted upon them afterwards by their lords. Economically and socially, the consequences were dramatic: whole communities were bankrupt and unable to pay proper taxes for a long time, the legal position of peasants was not to be altered for another 300 years, and due to the large number of outlawed peasants trying to survive by illegal means, such as robbery, commerce was severely hindered. This instability was one of the factors that lead to Upper Swabia's becoming a plaything of marauding armies during the Thirty Years War 1618 - 1648. Military actions followed by disease, such as the plague, led to a severe depopulation of Upper Swabia. After the end of the war, the Catholic Church intensified its efforts to regain ground from the Protestants. These efforts are known