[2] In 1635, Polish King Władysław IV Vasa resided at the castle during his stay in the city as the suzerain of Ducal Prussia.

Until the latter part of World War II, the apartments of the Hohenzollerns and the Prussia Museum (north wing, Prussia-Sammlung [de]) were open to the public daily.

During World War II, various pieces of captured Russian art were stored there, possibly including parts of the Amber Room.

[5] However, the thick walls were able to withstand both the aerial bombing and Soviet artillery, as well as urban fighting in April 1945, allowing the ruins of the castle to stay standing.

[7][8] However, the ruins of the nearby Königsberg Cathedral, which included the tomb of Immanuel Kant, were left standing, and, after the collapse of the USSR, in the late 1990s and early years of the 21st century were rebuilt and restored.

Continuation of development was stopped in the 1980s as the massive building gradually sank into the structurally unsound soil stemming from the collapse of tunnels in the old castle's subterranean levels.

The current Kaliningrad city administration debated whether to rebuild the castle with the financial assistance of the Russian Department of Culture.

In June 2010, the regional Minister of Culture, Mikhail Andreyev, announced that a referendum on the reconstruction of the castle would be held in the city of in March 2011.

[10][11] Since September 2001, the German magazine Der Spiegel has financed the excavation of parts of the castle's cellar, which was carried out with the Kaliningrad Regional Museum of History and Arts.