Historical Archive of the City of Cologne included copies of the protocols of the diets of the Hanseatic League. With the 1594 transfer, the Cologne archive became the most important repository of historical material concerning the Hanseatic League and thus concerning the history of Northern Germany in general, only matched by the municipal archives of Lübeck. On 27 February 1602, the city council ordered that books on jurisdiction and administration were to be systematically bought at the regularly held Frankfurt Book Fair. These were subsequently stored in the municipal archive and became the basis of the Cologne municipal library. The "Ratsbibliothek" was one of the few Cologne
History of Cologne In 1074 the commune was formed. By the 13th century, the relationship between the city and its archbishop had become difficult, and after the Battle of Worringen in 1288, the forces of Brabant and the citizenry of Cologne captured Archbishop Siegfried of Westerburg (1274–97), resulting in almost complete freedom for the city. To regain his liberty the archbishop recognized the political independence of Cologne but reserved certain rights, notably the administration of justice. Cologne effectively became a free city after 1288, and in 1475 it was formally made a free imperial city, a status that it held until annexed by