League and a first Swabian League were formed in 1381, merging into the South German League (Süddeutscher Städtebund) still in the same year. The League was a military defense pact against the nobility. Peace was made in the Treaty of Heidelberg on 26 July 1384. 1412. Pentapolitana was a 15th-century alliance of the five most important Hungarian royal free cities (now eastern Slovakia): Kassa (today Košice), Bártfa (Bardejov), Lőcse (Levoča), Eperjes (Prešov), and Kisszeben (Sabinov). 1440. The Prussian Confederation () was formed on 21 February 1440 at Marienwerder by a group of 53 nobles and clergy and 19 cities in Prussia, to oppose the Teutonic Knights. It was based on the basis of an earlier similar organization, the Lizard Union established in 1397 by Chełmno Land nobles. 1488. The Swabian League (Schwäbischer Bund) was a mutual defence and peace keeping association of Imperial Estates – free Imperial cities, prelates, principalities and knights – principally in the territory of the early medieval stem duchy of Swabia, established in 1488 at the behest of Emperor Frederick III of Habsburg and supported as well by Bertold von Henneberg-Römhild, archbishop of Mainz, whose conciliar rather than monarchic view of the Reich often put him at odds with Frederick's successor Maximilian. The Swabian League cooperated towards the keeping of the imperial peace and at least in the beginning curbing the expansionist Bavarian dukes from the House of Wittelsbach and the revolutionary threat from the south in the form of the Swiss. The League held regular meetings, supported tribunals and maintained a unified force of 12,000 infantrymen and 1200 cavalry. References See also Medieval commune Free imperial city Gray League Confederation of Cologne Covenant of Mayors Medieval Holy Roman Empire Medieval cities Medieval politics