A castle site in the Harz region where Otto IV died in 1218.
Harzburg was a royal fortress in the Harz Mountains of central Germany. Henry IV built it as a primary Saxon residence in the 1060s; its destruction by Saxon rebels in 1073 contributed to the conditions that led to the Investiture Controversy.
Otto IV, Holy Roman Emperor, died at Harzburg in 1218 after his political defeat and imperial eclipse following the Battle of Bouvines in 1214.
Harzburg thus marks both the beginning and the end of important episodes in German imperial history — Henry IV's confrontation with the Saxon nobility and Otto IV's final years after losing imperial legitimacy to Frederick II. The two events are separated by nearly 150 years but both reflect the contested nature of royal authority in the German lands.