The first churches on site of St. Peter's Church were built during the Middle Ages (1128-1369), with famous church leader Bishop Otto von Bamberg resident in 1128, with services and baptisms being held in Wolgast. von Bamberg ordered the razing of the Pagan temple on the site and the construction of the first church, which is thought to have been comprised of wooden polls. With the conferral of a town charter by nearby power Lübeck in 1282, this church was replaced by a Brick Gothic hall church. Over the course of two centuries, between 1369 and 1554, this second St. Peter's was replaced by a third church bearing the same name, built as a court church for the Duchy in a three-aisled Brick Gothic form, complete with ambulatory and inner apse. Just before the end of the ongoing construction, the main aisle was extended west from the upper bay.
In the first half of the 15th century, the side aisles were installed and parts of the wall of former church were incorporated into the building. In the last quarter of the 15th century, two side chapels were added to the building's southern wing, only to be followed shortly thereafter by the Danish pillaging of the town.
History has not been kind to St. Peter's. in 1713, Tsar Peter I of Russia ordered the destruction of the town; St. Peter's was almost completely burnt to the ground, except for the southern side aisle and both southern chapels. The collapsed tower destroyed all the buildings vaulting apart from those in the remains of the church. The church was energetically rebuilt in the years thereafter, with the upper part of the spire rebuilt in an ortagonal form; a slanted roof complete with lighting and a peak was added in the later work.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.