of all of its Prussian lands, the Teutonic Order retained its territories within the Holy Roman Empire and Livonia, although the Livonian branch retained considerable autonomy. Many of the Imperial possessions were ruined in the German Peasants' War from 1524 to 1525 and subsequently confiscated by Protestant territorial princes. The Livonian territory was then partitioned by neighboring powers during the Livonian War; in 1561 the Livonian Master Gotthard Kettler secularized the southern Livonian possessions of the Order to create the Duchy of Courland, also a vassal of Poland. After the loss of Prussia in 1525, the Teutonic Knights concentrated on their possessions in the Holy Roman Empire. Since they held no contiguous territory, they developed a three-tiered administrative system: holdings were combined into commanderies that were administered by a commander (Komtur). Several commanderies were combined to form a bailiwick headed by a Landkomtur. All of the Teutonic Knights' possessions were subordinate to the Grand Master, whose seat was in Bad Mergentheim. There were twelve German bailiwicks: Thuringia; Alden Biesen (in present-day Belgium); Hesse; Saxony; Westphalia; Franconia; Koblenz; Alsace-Burgundy; An der Etsch und im Gebirge (in Tyrol); Utrecht; Lorraine; and Austria. Outside of German areas were the bailiwicks of Sicily; Apulia; Lombardy; Bohemia; "Romania" (in Greece); and Armenia-Cyprus. The Order gradually lost control of these holdings until, by 1809, only the seat of the Grand Master at Mergentheim remained. Following the abdication of Albert of Brandenburg, Walter von Cronberg became Deutschmeister in 1527, and later Administrator of Prussia and Grand Master in 1530. Emperor Charles V combined the two positions in 1531, creating the title Hoch- und Deutschmeister, which also had the rank of Prince of the Empire. A new Grand Magistery was established in Mergentheim in Württemberg, which was attacked during the German Peasants' War. The Order also helped Charles V against the Schmalkaldic League. After the Peace of Augsburg in 1555, membership in the Order was open to Protestants, although the majority of brothers remained Catholic. The Teutonic Knights became tri-denominational, with Catholic, Lutheran and Reformed bailiwicks. The Grand Masters, often members of the great German families (and, after 1761, members of the House of Habsburg-Lorraine), continued to preside over the Order's considerable holdings in Germany. Teutonic Knights from Germany, Austria, and Bohemia were used as battlefield commanders leading mercenaries for the Habsburg monarchy during the Ottoman wars in Europe. The military history of the Teutonic Knights was to