Aachen, in the northern foothills of the Ardennes, is the city of coronations. Between 936 and 1531, thirty German princes were crowned King of Germany in the cathedral. It then lost this privilege to Frankfurt. Charlemagne chose Aachen as the permanent home of the Frankish court. In 800, he was crowned Holy Roman Emperor. His court became a font of learning and its religious schools helped the spread of culture and Christianisation.