Casimir III the Great

Casimir ensured stability and great prospects for the future of the country. He established the Corona Regni Poloniae – the Crown of the Polish Kingdom,[7] which certified the existence of the Polish lands independently from the monarch. Prior to that, the lands were only the property of the Piast dynasty.

At the Sejm in Wiślica, on 11 March 1347, Casimir introduced reforms to the Polish judicial system and sanctioned civil and criminal codes for Great and Lesser Poland, earning the title "the Polish Justinian".[3] In 1364, given the permission from pope Urban V, Casimir established the University of Kraków, the oldest Polish University.[10] It was regarded a rare distinction, since it was the second university founded in Central Europe, after the Charles University in Prague.[7]

Casimir demonstrated competence in foreign diplomacy and managed to double the size of the kingdom. He neutralized the relations with potential enemies in the West and the North, and set on an expansion eastward. He conquered the Ruthenian kingdom of Halych and Volodymyr (a territory in the modern-day Ukraine), known in Polish history as Red Ruthenia and Volhynia. By extending the borders far south-east, the Polish kingdom gained access to the lucrative Black Sea trade.[11]

In 1355, in Buda, Casimir designated his nephew Louis I of Hungary as his successor should he produce no male heir, just as his father had with Charles I of Hungary to gain help against Bohemia. In exchange Casimir gained a favourable Hungarian attitude, needed in disputes with the hostile Teutonic Order and the Kingdom of Bohemia. At the time Casimir was 45 years old, and so producing a son did not seem unreasonable (he already had a few children).[12]

Casimir left no legal son, however, begetting five daughters instead. He tried to adopt his grandson, Casimir IV, Duke of Pomerania, in his last will. The child had been born to his eldest daughter, Elisabeth, Duchess of Pomerania, in 1351. This part of the testament was invalidated by Louis I of Hungary, however, who had traveled to Kraków quickly after Casimir died (in 1370) and bribed the nobles with future privileges. Casimir III also had a son-in-law, Louis VI of Bavaria, Margrave and Prince-elector of Brandenburg, who was considered a possible successor, but he was deemed ineligible as his wife, Casimir's daughter Cunigunde, had died in 1357 without issue.[13]

Thus King Louis I of Hungary became successor in Poland. Louis was proclaimed king upon Casimir's death in 1370, though Casimir's sister Elisabeth (Louis's mother) held much of the real power until her death in 1380.[14]

On 30 April or 16 October 1325, Casimir married Aldona of Lithuania.[17] She was also known as Anna, possibly a baptismal name. She was a daughter of Grand Duke Gediminas of Lithuania and Jewna. They had two children:

• Elisabeth of Poland (ca. 1326–1361); married Duke Bogislaus V of Pomerania
• Cunigunde of Poland (1334–1357); married Louis VI the Roman, the son of Louis IV, Holy Roman Emperor

Aldona died on 26 May 1339. Casimir remained a widower for two years.

On 29 September 1341, Casimir married his second wife, Adelaide of Hesse. She was a daughter of Henry II, Landgrave of Hesse, and Elizabeth of Meissen. They had no children. Casimir started living separately from Adelaide soon after the marriage. Their loveless marriage lasted until 1356, when he declared himself divorced.[18]

After Casimir "divorced" Adelaide he married his mistress Christina Rokiczana, the widow of Miklusz Rokiczani, a wealthy merchant. Her own origins are unknown. Following the death of her first husband she had entered the court of Bohemia in Prague as a lady-in-waiting. Casimir brought her with him from Prague and convinced the abbot of the Benedictine abbey of Tyniec to marry them. The marriage was held in a secret ceremony but soon became known. Queen Adelaide renounced it as bigamous and returned to Hesse. Casimir continued living with Christine despite complaints by Pope Innocent VI on behalf of Queen Adelaide. This marriage lasted until 1363–64 when Casimir again declared himself divorced. They had no children.[19]

In about 1365, Casimir married his fourth wife Hedwig of Żagań. She was a daughter of Henry V of Iron, Duke of Żagań and Anna of Mazovia. They had three children:

• Anna of Poland, Countess of Celje (1366 – 9 June 1422); married firstly William of Celje; their only daughter was Anne of Celje, who married Jogaila of Lithuania when he was king of Poland (as Władysław II Jagiełło). Anna married secondly Ulrich, Duke of Teck; they had no children.
• Kunigunde of Poland (1367 – 1370)
• Jadwiga of Poland (1368 – ca. 1382)

As Adelheid was still alive (and possibly Christina as well), the marriage to Hedwig was also considered bigamous. Because of this, the legitimacy of his three young daughters was disputed.[20] Casimir managed to have Anna and Kunigunde legitimated by Pope Urban V on 5 December 1369. Jadwiga the younger was legitimated by Pope Gregory XI on 11 October 1371 (after Casimir's death).[21]

• Casimir III the Great is one of the main characters in Polish historical drama series Korona królów (The Crown of the Kings). He is played by Mateusz Król (season 1) and Andrzej Hausner (season 2).[23]
• Casimir III the Great is mentioned in a speech by Amon Göth in the film Schindler's List.[24]

• Casimir features as a playable leader in the 2010 strategy game Civilization V, having been added in its 2013 expansion, Brave New World.
• Casimir also features as a ruler in the strategy game Crusader Kings II.

• Casimir is featured on the obverse of the 50 Polish złoty banknote, with his regalia on the reverse.[25]