The Croatian National Theatre (Croatian: Hrvatsko narodno kazalište u Osijeku) is a theatre building in Osijek capital of the Croatian region of Slavonia.Opened in 1866 and the building was expanded and fully completed in 1907 according to the plans of its local architect Karlo Klausner. Designed in baroque style and exterior it was damaged by the JNA during the Croatian War of Independence in the 1990s and has been extensively restored.