Bishop Arnaldur (1124-52) returned to Norway in 1150 from Gardar, Greenland and was appointed first Bishop of Hamar. He began to build the cathedral, which was completed about the time of Bishop Paul (1232-52). Bishop Thorfinn of Hamar (1278-82) was exiled and died at Ter Doest in Flanders. Thorfinn and many other bishops of the area disagreed with the sitting King Eric II of Norway regarding a number of issues, including episcopal elections. Bishop Jörund (1285-86) was transferred to Trondhjem.
In the aftermath of the Reformation in Norway, the structure was renamed Hamarhus fortress and made into the residence of the sheriff. The cathedral was still used but fell into disrepair culminating with the Swedish army’s siege and attempted demolition in 1567, during the Northern Seven Years' War. Swedish forces had launched attacks into Eastern Norway, capturing Hamar and continued towards Oslo. The Swedes later retreated, torching Hamar on their way, destroying Hamar Cathedral and Hamarhus.
Today the ruins of Hamar Cathedral form a part of the Hedmark museum (Hedmarksmuseet). The ruins of what remain of the Hamar cathedral, were originally built in Romanesque architecture and later converted to Gothic architecture. The distinctive arches in the cathedral ruins are covered in one of the most ambitious construction projects of its kind undertaken by the Norwegian government.References:
German crusaders known as the Livonian Brothers of the Sword began construction of the Cēsis castle (Wenden) near the hill fort in 1209. When the castle was enlarged and fortified, it served as the residence for the Order's Master from 1237 till 1561, with periodic interruptions. Its ruins are some of the most majestic castle ruins in the Baltic states. Once the most important castle of the Livonian Order, it was the official residence for the masters of the order.
In 1577, during the Livonian War, the garrison destroyed the castle to prevent it from falling into the control of Ivan the Terrible, who was decisively defeated in the Battle of Wenden (1578).
In 1598 it was incorporated into the Polish-Lithuanian Commonwealth and Wenden Voivodship was created here. In 1620 Wenden was conquered by Sweden. It was rebuilt afterwards, but was destroyed again in 1703 during the Great Northern War by the Russian army and left in a ruined state. Already from the end of the 16th century, the premises of the Order's castle were adjusted to the requirements of the Cēsis Castle estate. When in 1777 the Cēsis Castle estate was obtained by Count Carl Sievers, he had his new residence house built on the site of the eastern block of the castle, joining its end wall with the fortification tower.
Since 1949, the Cēsis History Museum has been located in this New Castle of the Cēsis Castle estate. The front yard of the New Castle is enclosed by a granary and a stable-coach house, which now houses the Exhibition Hall of the Museum. Beside the granary there is the oldest brewery in Latvia, Cēsu alus darītava, which was built in 1878 during the later Count Sievers' time, but its origins date back to the period of the Livonian Order. Further on, the Cēsis Castle park is situated, which was laid out in 1812. The park has the romantic characteristic of that time, with its winding footpaths, exotic plants, and the waters of the pond reflecting the castle's ruins. Nowadays also one of the towers is open for tourists.