Weesenstein castle was erected here sometime around 1200, built with the purpose of defending the border to the Kingdom of Bohemia; it was mentioned in written sources for the first time in 1318. The oldest part of the presently visible castle is its central round tower, erected sometime around 1300. The castle was built for the burgraves of Dohna; the burgraviate was incorporated in the Margraviate of Meissen in 1400 and in 1406 the castle was transferred by the margrave to the von Bünau family in gratitude for their support in the Dohna Feud.
The Bünau family transformed the defensive castle into a residential Schloss in 1526–1575, and successive generations would expand and rebuild the Schloss in stages. It continued to be the main seat of the family for about 350 years. As a consequence of the Seven Years' War of 1756–1763 the family however lost a substantial part of their wealth and had to part with the castle which subsequently passed into the hands of the von Uckermann family. The Uckermann family owned the castle for two generations and continued the process of embellishing the estate, not least the garden.
From 1830, the Schloss was used by the rulers of Saxony, the House of Wettin. Several members of the royal family lived in the castle, including three kings: Anthony of Saxony, John of Saxony and George of Saxony. After World War I, the castle was sold and in 1933 became the seat of an association for the protection of the heritage of Saxony. During World War II, the castle was used for safekeeping most of the art collections of the Dresden State Art Collections. Because of this, the castle and its contents were spared from destruction during the bombing of Dresden in World War II. After the war, the castle was used to house refugees before it was taken over by the state.
Today it belongs to the state-owned company State Palaces, Castles and Gardens of Saxony. It houses a museum and 35 of the rooms of the castle are open to the public.
The presently visible ensemble is the product of centuries of development and rebuilding. The castle is thus a mix of styles, ranging from Gothic architecture to Classical architecture. The main portal, built in 1575, is considered one of the most valuable Renaissance portals in Saxony, The Schloss is built on a rock with storeys descending from the central, medieval round tower (with its 18th-century spire). In total, the castle has eight storeys.
The castle contains around 200 rooms in total. The Baroque chapel, described as the 'architectural and artistic highlight of the entire castle', is thought to have been designed by Johann George Schmidt. A formal garden lies adjacent to the castle. An English landscape garden, one of the earliest to be created in Saxony (c. 1780), has since been overgrown.References:
Ängsö Castle was first named as "Engsev" in a royal charter by king Canute I of Sweden (r. 1167-1196), in which he stated that he had inherited the property after his father Eric IX of Sweden. Until 1272, it was owned by the Riseberga Abbey, and then taken over by Gregers Birgersson.
From 1475 until 1710, it was owned by the Sparre family. The current castle was built as a fortress by riksråd Bengt Fadersson Sparre in the 1480s. In 1522, Ängsö Castle was taken after a siege by king Gustav Vasa, since its owner, Fadersson's son Knut Bengtsson, sided with Christian II of Denmark. However, in 1538 it was given by the king to Bengtsson's daughter Hillevi Knutsdotter, who was married to Arvid Trolle.
In 1710, the castle was taken over by Carl Piper and Christina Piper. Ängsö Castle was owned by the Piper family from 1710 until 1971, and is now owned by the Westmanna foundation. The castle building itself was made into a museum in 1959 and was made a listed building in 1965. It is currently opened to visitors during the summers.
The castle is a cubical building in four stores made by stone and bricks. The lower parts is preserved from the middle ages. It was redecorated and expanded in the 1630s. The 4th storey as well as the roof is from the expansion of Carl Hårleman from 1740-41. It gained its current appearance in the 1740s.