| Native Name: | Księstwo ziębickie (pl) Herzogtum Münsterberg (de) Minstrberské knížectví (cs) |
| Conventional Long Name: | Duchy of Münsterberg |
| Common Name: | Münsterberg |
| Era: | Middle Ages Early modern period |
| Status: | Silesian duchy |
| Symbol: | Coat of arms of Silesia |
| Year Start: | 1321 |
| Year End: | 1791 |
| Life Span: | 1321–1791 |
| Event Start: | Partitioned from |
| Event1: | Vassalized by Bohemia |
| Date Event1: | 1336 |
| Event2: | Enfeoffed to Podiebrad family |
| Date Event2: | 1456 |
| Event3: | To Principality of Auersperg |
| Date Event3: | 1654 |
| Event4: | Incorporated into Prussia |
| Date Event4: | 1742 |
| Event End: | Seized by Hohenzollern |
| P1: | Duchy of Jawor |
| S1: | Kingdom of Prussia |
| Flag S1: | Flag of the Kingdom of Prussia (1750-1801).svg |
| Image Map Caption: | Silesia in the years 1322–1331, Duchy of Münsterberg (Ziębice) under its first ruler, Bolko II of Ziębice, marked in purple |
| Capital: | Ziębice |
| Today: | Poland |
The Duchy of Münsterberg (German: Herzogtum Münsterberg) or Duchy of Ziębice (Polish: Księstwo Ziębickie, Czech: Minstrberské knížectví) was one of the Duchies of Silesia, with a capital in Münsterberg (Ziębice). Existing from 1321/1322 to 1742, it was located in what came to be referred to as Lower Silesia. Its territory is similar to modern Ząbkowice Śląskie County in Poland.
After the death of Henry IV in 1290, during the period of fragmentation of Poland, Bolko I the Strict inherited the towns of Münsterberg (Ziębice) and Frankenstein (Ząbkowice Śląskie). Around 1300, he finished a castle in Münsterberg. When he died in 1301, his possessions were divided among his three sons. The youngest son, Bolko II Ziębicki, received Münsterberg (Ziębice) in 1321 and was the first to style himself Duke of Münsterberg (Duke of Ziębice). He resided in the town's castle. After he demanded land from the diocese's domains, a long-running dispute with the Bishop of Breslau arose, and the bishop imposed an interdict over the duchy several times, while the duke was anathematized. After the siege of Frankenstein by the Moravian Margrave and later by Holy Roman Emperor Charles IV, Bolko II recognized Bohemian suzerainty on 29 August 1336 in the Treaty of Straubing. Bolko II died in 1341; he was buried in the church of the Henryków monastery, a monastery he generously supported during his lifetime.
Bolko's son, Nicholas the Small, was Duke of Münsterberg until 1358. In the year of his father's death, he paid homage to Bohemian King John of Luxembourg and his son Charles. Nicholas' successor, Bolko III, died in 1410. The next dukes, the brothers Henry († 1420) and Jan, ruled the duchy together until 1420; afterward Jan ruled alone. Jan died on 27 December 1428 at the Battle of Altwilmsdorf against the Hussites. With him the Piast Dukes of Münsterberg died out.
With the death of Duke Jan, the duchy passed to Bohemian King Sigismund, who pledged it to Půta III of Častolovice, Lord of Častolovice, in 1429. After Půta III's death in 1434, his widow, Anna of Koldice, kept the bond and ruling claims. However, the estates of Münsterberg favored Countess Euphemia of Oettingen, a niece of the last duke. She gained Münsterberg in 1435, but abandoned it a year later because of continuing disputes. Although Anna of Koldice sold her possessions in 1440 to Hynek Krušina of Lichtenburg, whom she married shortly thereafter, new succession disputes with the estates erupted, in which several Silesian princes supported the estates of Münsterberg. In 1442, Hynek Krušina looted the Heinrichau monastery, since it was particularly associated with the estates. After lengthy negotiations, the estates of Münsterberg on 25 April 1443 chose Duke Vilém of Opava as their new ruler. His claims were justified by two reasons. First, he was the son of Přemysl of Opava of the Přemyslid dynasty and Catherine, the sister of Jan of Ziębice († 1428), the last duke of Münsterberg of the Piast dynasty. Second, he was married to Salome, a daughter of the late Půta III. Vilém joined forces with the Bishop of Wroclaw and the Silesian princes, who fought against Hynek Krušina. Although Hynek Krušina had not legally abandoned his claims, the dispute was settled in 1444.After Vilém's death in 1452, the duchy passed to his brother Arnošt, who sold it in 1456 to Bohemian King George of Poděbrady. The King handed his possessions down to his sons Victor, Henry the Elder and Henry the Younger in 1472. Henry the Elder, who was married to Ursula of Brandenburg, a daughter of Elector Albrecht III of Brandenburg, received the Duchy of Münsterberg. He also got Frankenstein (Ząbkowice Śląskie), the County of Kladsko, the dominion of Náchod, and the former east Bohemian possessions of Půta III. In 1488, he built a castle in Münsterberg and in 1495 obtained the duchy of Oels. He resided in Kladsko (Glatz, Kłodzko), where he died in 1498.
He was succeeded by his sons Albert, George and Charles, who ruled together. The latter moved his residence to Frankenstein in 1530, where he died six years later and was buried in the parish church. His sons, Joachim, Henry, John and George, supporters of the Reformation, ruled jointly until 1542. In the same year, they pledged the indebted duchy to their uncle, Duke Frederick II of Legnica († 1547). In 1551, Bohemian King Ferdinand I redeemed the duchy from Duke Frederick III of Legnica. Between 1552 and 1559 it belonged to Queen Isabella of Hungary as a pledged lordship. In 1559, the duchy passed into the hands of Duke John of Oels, a son of Charles I of Münsterberg, and thus returned to the house of Poděbrady.
After John's successor, Charles Christopher, died childless in 1569, Münsterberg reverted to the crown of Bohemia. Because of his contributions to the House of Habsburg, King Ferdinand III in 1654 gave the duchy to a Prince of the Holy Roman Empire, Count Johann Weikhard of Auersperg.
After the First Silesian War and the incorporation of Silesia into Prussia in 1742, the Auerspergs retained their possessions. The duchy however was converted into a State country. In 1791, Prince Charles Joseph Anton of Auersperg sold the duchy to Prussian King Frederick William II.
The duchy passes to Bohemian king Sigismund.