1015 First documented mention of Plesse Castle as the property of Bishop Meinwerk of Paderborn, who bequeathed the Plesse to his church.
Around 1150, the Lords of Höckelheim moved their residence to Plesse Castle and from then on called themselves "von Plesse." For more than 400 years, the castle was their residence, administrative center, and center of power.
1192 – Emperor Henry VI exchanged Desenberg Castle with the Paderborn Church for Plesse Castle. This exchange was reversed in 1195.
13th/14th century. The Plesse lordship resisted the expansion of the Duchy of Brunswick and later formed an independent territory within the duchy. The approximately 50 people were supplied by a domain at the foot of the castle hill.
``` 1571 – The noble Plesse family dies out, and the castle passes to the Landgraves of Hesse according to an inheritance contract.
1624 – Landgrave Moritz of Hesse, having fled Kassel during the Thirty Years' War, resides at Plesse Castle. The castle offers shelter to the inhabitants of the surrounding villages during this time. In 1627, it is besieged by imperial troops.
Around 1660, the residents abandon the castle after the official residence passes to the town of Bovenden. Since then, the castle has continued to decay. The walls are forgotten, and legends and ghost stories revive the imagination surrounding the ruins.
Around 1760, the ruins experience new interest and life. They become a popular destination for the people of Göttingen and members of the university.
1815 – During the Congress of Vienna, Plesse Castle is incorporated into the Kingdom of Hanover, which becomes part of Prussia from 1866 onwards.
1821 – Gradually established monument protection protects the ruins from further decay, and the "Little Tower" is secured.
1853 – King George V and his wife, Queen Marie of Hanover, visit the Plesse and, in the following years, provide substantial funds to advance the restoration. At the king's instigation, a restaurant is established.
1980 – The Herrenbau is restored, the vaulted cellar is exposed, and the restaurant is incorporated.
2005 – The restaurant reopens under the direction of Mrs. Huberta Zornhagen.