The reason for moving from city to city was mainly political. Although his experiment was short-lived, Frederic successfully created the first modern state in Europe, run by an efficient bureaucracy: its members were neither appointed from the aristocracy nor the clergy with good reason, since the former were far more interested in defending their own privileges than the welfare of the country and often plotted against him in the hope of regaining their power, while the latter were basically faithful to the Pope, his biggest enemy.