Marienburg
In the history of the Warhammer World, Marienburg was once part of the Empire, but gained independence though a massive transfer of gold into the imperial coffers during the reign of the corrupt Emperor Dieter IV. Any subsequent attempts to subdue Marienburg and bring it back within rule of the Empire have failed, and today Marienburg remains a fiercely independent city-state where the Count of Nordland, nominally the ruler of Marienburg, is forbidden to return under pain of death.
Graf Paulus van der Maacht was the last Baron of Westerland. He was killed in 2302IC during the last Incursion of Chaos. He was 15 years old and unmarried, leaving no heir to the Barony. The van der Maachts were also a junior branch of the ruling house of Nordland who immediately put forward candidates upon Paulus' death. So did many other houses from right across the Empire. The decision of Magnus the Pious over whom to appoint looked ready to destabilise the Empire. It was at this point that the three envoys, Jan Koopmans, Pieter Winkler, and Thijs van Onderzoeker from Marienburg's merchant families entered the scene.
In 2305IC Magnus the Pious created the Province of the Westerland from the Barony of Westerland. The Province was to be governed by a Council made up of the heads of the merchant families of Marienburg. For over a hundred years this council operated successfully but they had insidiously extended their powers, allowing merchant princes to keep private fleets and militias (in order to protect the Province from pirates). In 2378–79 IC a successful campaign against the privateers was brought to a close but still the fleets and armies did not disband. The key point was when the Council approached Emperor Leopold and offered to relieve the Imperial Second Fleet (stationed at Marienburg) and conduct the defence of the city themselves. Leopold agreed as he was facing uprisings in other areas and the upkeep of the Second Fleet was a drain of the Imperial coffers he could do without. The council also relieved the Imperial Excise men of their duties and collected taxes themselves on behalf of the Emperor. In the spring of 2429 IC the Province of Westerland refused to provide any more troops for the Imperial armies and when Emperor Dieter IV was replaced by Prince Wilhelm of Altdorf, Westerland formally seceded from the Empire. The city is now ruled over by the High Council.