Mikulov Castle (German: Nikolsburg) is a castle in the town of Mikulov in South Moravian Region of the Czech Republic. The castle stands on a place of historic Slavonic settlement, where since the end of the 13th century the original stone castle was erected. Henry I, lord of Liechtenstein and Petronell (d. 1265) was given the lordship of Mikulov (Nikolsburg) as free property from Ottokar II of Bohemia, whom he supported politically, in 1249. Nikolsburg Castle was sold by the House of Liechtenstein in 1560 and then became the main seat of the princes of Dietrichstein.
The present castle is the result of a reconstruction in 1719–1730 under this family. The daughter of the 9th Prince married General Count Alexander von Mensdorff-Pouilly, Minister of Foreign Affairs, who was created Fürst (prince) of Dietrichstein and Nikolsburg in 1869.
The end of World War II meant a complete disaster for the castle, as it was destroyed by fire whose origins are unclear. The Mensdorff-Dietrichstein family was expropriated by the new communist government.
During the war, the anthropological collection from the Moravské zemské muzeum had been moved to Mikulov Castle for safekeeping purposes. Many of the most important discoveries from Předmostí u Přerova, Dolní Věstonice and the Mladeč caves were destroyed by the fire.After an extensive reconstruction in the 1950s, the castle became the seat of the Regional Museum in Mikulov, housing art and historical collections, including artifacts relating to the history of local wine production. The Renaissance wine barrel, dating from 1643 and one of the largest, 1,014 hectolitres (22,300 imp gal; 26,800 US gal), wine barrels in Central Europe, is on display.