<P> Waldensians are considered a forerunner to the Protestant Reformation, and they melted into Protestantism with the outbreak of the Reformation and became a part of the wider Reformed tradition after the views of John Calvin and his theological successors in Geneva proved very similar to their own theological thought . Waldensian churches still exist, located on several continents . </P> <P> In Northern Europe, the Hanseatic League, a federation of free cities to advance trade by sea, was founded in the 12th century, with the foundation of the city of Lübeck, which would later dominate the League, in 1158--1159 . Many northern cities of the Holy Roman Empire became hanseatic cities, including Amsterdam, Cologne, Bremen, Hanover and Berlin . Hanseatic cities outside the Holy Roman Empire were, for instance, Bruges and the Polish city of Gdańsk (Danzig), as well as Königsberg, capital of the monastic state of the Teutonic Knights . In Bergen, Norway and Veliky Novgorod, Russia the league had factories and middlemen . In this period the Germans started colonising Europe beyond the Empire, into Prussia and Silesia . </P> <P> In the late 13th century, a Venetian explorer named Marco Polo became one of the first Europeans to travel the Silk Road to China . Westerners became more aware of the Far East when Polo documented his travels in Il Milione . He was followed by numerous Christian missionaries to the East, such as William of Rubruck, Giovanni da Pian del Carpine, André de Longjumeau, Odoric of Pordenone, Giovanni de' Marignolli, Giovanni di Monte Corvino, and other travellers such as Niccolò de' Conti . </P> <P> Philosophical and scientific teaching of the Early Middle Ages was based upon few copies and commentaries of ancient Greek texts that remained in Western Europe after the collapse of the Western Roman Empire . Most of them were studied only in Latin as knowledge of Greek was very limited . </P>

Major towns and cities in the high middle ages