The profitable mines remained a "Reichsgut" directly belonging to the Holy Roman Emperor. When in 1175 Emperor Frederick Barbarossa called for support on his campaign against the Italian cities of the Lombard League, the Welf duke Henry the Lion demanded his enfeoffment with the Goslar mines in return, which Frederick denied. Duke Henry laid siege to the town and had the mining installations demolished. Restored after his deposition in 1180, the Rammelberg mines were again contested in 1198/99 during the Welf-Hohenstaufen throne quarrel between his son Otto IV and Frederick's son Philip of Swabia.