Reichsacht
In 1166, Aachen was given imperial immediacy and declared a Free Imperial City of the Holy Roman Empire by Emperor Frederick I, called "Barbarossa", by means of the "Charlemagne Privilege" ("Karlsprivileg"). Aachen played a part in the league which kept the peace between 1351 and 1387 between the Meuse and the Rhine. In 1450 a rebellion led to the acceptance of the guilds to a share in local government. In the 16th century Aachen began declining in importance and prosperity. It was too close to the Kingdom of France frontier to be safe, and too far from the Holy Roman Empire to be convenient as a capital city. In 1562 the Imperial election and Coronation of the Holy Roman Emperor Maximilian II took place at Frankfurt, a precedent followed until the end of the Holy Roman Empire. The Protestant Reformation brought trouble to Aachen. In 1580 Protestantism got the upper hand; an Imperial ban resulted and was imposed in 1598 by Ernest of Bavaria, archbishop-elector of Cologne. A religious relapse of the city led to a new Imperial ban by Emperor Matthias in 1613, and in 1614 Ambrogio Spinola's Spanish Army forced the recalcitrant city back into the Catholic fold. In 1656 a great fire destroyed 4,000 houses. This calamity completed the ruin started by the Thirty Years' War.