A deed by Emperor Frederick I Barbarossa in 1155 confirmed the princely status of the bishop and of his bishopric as an Imperial Estate. The territory of the prince-bishopric contracted during the following centuries under pressure from both the Swiss Confederacy and the House of Habsburg. Furthermore, the city of Konstanz was granted the status of a free imperial city and from then on the bishop's sovereignty in the city was restricted to a small area around the cathedral church. In 1527, during the Protestant Reformation, the administrative seat of the Prince-Bishop was finally moved to Meersburg across Lake Constance. However, Konstanz fell to the Counter-Reformation induced by the Habsburgs, who eventually abolished its status as a free imperial city and incorporated it into their Further Austrian possessions in 1548.