It has a long history dating back to the 12th century. In 1429 it came, through inheritance, into the hands of its neighbouring county of Stolberg. When in 1645 the Stolberg-Stolberg line was split up, Wernigerode became the seat of the County Stolberg-Wernigerode. However, due to the Thirty-Years War, it was Isenburg which became the residence of the ruling count. This lasted until 1710, when the seat was relocated back to Wernigerode. The castle was rebuilt in Baroque style.

However it was in the second half of the 19th century that the castle got his present form and outlook in the Neo-Romantic style (Historismus). The transformation had been executed for Count and later Prince Otto zu Stolberg-Wernigerode, who had made a cometic career, first as president of the Prussian Province of Hanover (1867), then as president of the Prussian House of Lords (1872) and finally as German Vice-Chancellor (1878). The transformation was finished in 1893. 

The castle and estate were confiscated by the communists. Today it is owned by a foundation.

For detailed information concerning history, museum and cultural activities, see website.