The Church of St. Andreas was constructed between 1622 and 1629 in the South German baroque style. It was originally a Jesuit church and also served as the court church for the Counts palatine of Neuburg. After the dissolution of the Jesuit order in August 1773 it served as a parish church until 2005 when it became the monastery church of the Dominican Order. The building itself is now owned by the city of Düsseldorf.
The church is furnished with stucco by Johannes Kuhn from Strassburg and life-size sculptures of the apostles and of saints of the Society of Jesus.
In the late 17th and early 18th centuries, the church was an important center of musical culture in Düsseldorf. The composer Johann Hugo von Wilderer served as its organist. The mausoleum, designed by Venetian architect Simone del Sarto, contains the tombs of several Electors Palatine, including that of Johann Wilhelm. The high altar of the church was destroyed during World War II. The new altar, designed by Ewald Mataré was built in 1960. Paintings by Ernst Deger can be found in the church's two side altars which are dedicated to the Virgin Mary.References:
First record of Kastelholma (or Kastelholm) castle is from the year 1388 in the contract of Queen Margaret I of Denmark, where a large portion of the inheritance of Bo Jonsson Grip was given to the queen. The heyday of the castle was in the 15th and 16th centuries when it was administrated by Danish and Swedish kings and stewards of the realms. Kastelhoma was expanded and enhanced several times.
In the end of 16th century castle was owned by the previous queen Catherine Jagellon (Stenbock), an enemy of the King of Sweden Eric XIV. King Eric conquered Kastelholma in 1599 and all defending officers were taken to Turku and executed. The castle was damaged under the siege and it took 30 years to renovate it.
In 1634 Åland was joined with the County of Åbo and Björneborg and Kastelholma lost its administrative status.