sentences:  After the allied Lutheran princes had signed the Treaty of Chambord, their forces campaigned Tyrol in the Habsburg hereditary lands and forced Charles V to flee toward the Carinthian town of Villach.In August 1552 his younger brother Archduke Ferdinand I of Austria concluded the Peace of Passau, whereby he formally accepted the Lutheran Augsburg Confession, confirmed by the emperor himself in the 1555 Peace of Augsburg.Once the armistice with the Protestant princes was declared, Charles V during the Italian War of 1551–59 made several attempts to forcibly regain the overlordship over the Three Bishoprics, the disposal of which was his Imperial privilege.