King of Poland in the context of "Battle of Vienna"

The Dnieper–Bug Canal (alternatively the Dnepr-Bug Canal), or the Dneprovsko-Bugsky Canal, is the longest inland ship canal in Belarus. It connects the Mukhavets River (a tributary of the Bug River) and the Pina River (a tributary of the Pripyat River). It is managed by Dneprobugvodput.

The artificial channel dug between Kobryn and Pinsk was originally named the Royal Canal (Polish: Kanał Królewski), after the King of Poland Stanisław August Poniatowski (r. 1764–1795), who initiated its construction. It forms an important part of the transportation artery linking the Baltic Sea and the Black Sea. The total length of the canal system from Brest to Pinsk is 196 km (122 mi), including the 105 km (65 mi) long artificial waterway.

The Union of Lublin (Polish: Unia lubelska; Lithuanian: Liublino unija) was signed on 1 July 1569 in Lublin, Poland, and created a single state, the Polish–Lithuanian Commonwealth, one of the largest countries in Europe at the time. It replaced the personal union of the Crown of the Kingdom of Poland and the Grand Duchy of Lithuania with a real union and an elective monarchy, as Sigismund II Augustus, the last of the Jagiellons, remained childless after three marriages. In addition, the autonomy of Royal Prussia was largely abandoned. The Duchy of Livonia, tied to Lithuania in real union since the Union of Grodno (1566), became a Polish–Lithuanian condominium.

The Commonwealth was ruled by a single elected monarch who carried out the duties of King of Poland and Grand Duke of Lithuania, and governed with a common Senate and parliament (the Sejm). The Union is seen by some as an evolutionary stage in the Polish–Lithuanian alliance and personal union, necessitated also by Lithuania's dangerous position in wars with Russia.

Casimir III the Great (Polish: Kazimierz III Wielki; 30 April 1310 – 5 November 1370) reigned as the King of Poland from 1333 to 1370. He also later became King of Ruthenia in 1340, retaining the title throughout the Galicia–Volhynia Wars. He was the last Polish king from the Piast dynasty.

Casimir inherited a kingdom weakened by war and under his rule it became relatively prosperous and wealthy. He reformed the Polish army and doubled the size of the kingdom. He reformed the judicial system and introduced several undying codified statutes, gaining the title "the Polish Justinian". Casimir built extensively and founded the Jagiellonian University (back then simply called the University of Krakow), the oldest Polish university and one of the oldest in the world. He also confirmed privileges and protections previously granted to Jews and encouraged them to settle in Poland in great numbers.

Louis I, also known as Louis the Great (Hungarian: Nagy Lajos; Croatian: Ludovik Veliki; Slovak: Ľudovít Veľký) or Louis the Hungarian (Polish: Ludwik Węgierski; 5 March 1326 – 10 September 1382), was King of Hungary and Croatia from 1342 and King of Poland from 1370 until his death in 1382. He was the first child of Charles I of Hungary and his wife, Elizabeth of Poland, to survive infancy. A 1338 treaty between his father and Casimir III of Poland, Louis's maternal uncle, confirmed Louis's right to inherit the Kingdom of Poland if his uncle died without a son. In exchange, Louis was obliged to assist his uncle to reoccupy the lands that Poland had lost in previous decades. He bore the title Duke of Transylvania between 1339 and 1342 but did not administer the province.

Louis was of age when he succeeded his father in 1342, but his deeply religious mother exerted a powerful influence on him. He inherited a centralized kingdom and a rich treasury from his father. During the first years of his reign, Louis launched a crusade against the Lithuanians and restored royal power in Croatia; his troops defeated a Tatar army, expanding his authority towards the Black Sea. When his brother, Andrew, Duke of Calabria, husband of Queen Joanna I of Naples, was assassinated in 1345, Louis accused the queen of his murder and punishing her became the principal goal of his foreign policy. He launched two campaigns to the Kingdom of Naples between 1347 and 1350. His troops occupied large territories on both occasions, and Louis adopted the styles of Neapolitan sovereigns (including the title of King of Sicily and Jerusalem), but the Holy See never recognized his claim. Louis's arbitrary acts and atrocities committed by his mercenaries made his rule unpopular in Southern Italy. He withdrew all his troops from the Kingdom of Naples in 1351.

In a strict sense, the Union of Krewo or Act of Krėva (also spelled Union of Krevo, Act of Kreva; Polish: unia w Krewie; Lithuanian: Krėvos sutartis) comprised a set of prenuptial promises made at Kreva Castle on 14 August 1385 by Jogaila, Grand Duke of Lithuania, in regard to his prospective marriage to the underage reigning Queen Jadwiga of Poland.

Though very limited in scope, the "Union of Krewo", in historiography, often refers not only to the particular document but to events of 1385–1386 as a whole. After the 1385 negotiations, Jogaila converted to Christianity, married Jadwiga, and was crowned King of Poland in 1386.

Jogaila (Lithuanian: [jɔˈɡâːɪɫɐ] ; c. 1352/1362 – 1 June 1434), later Władysław II Jagiełło (Polish: [vwaˈdɨswaf jaˈɡʲɛwwɔ] ), was Grand Duke of Lithuania beginning in 1377 and starting in 1386, becoming King of Poland as well. As Grand Duke, he ruled Lithuania from 1377 to 1381 and from 1382 to 1401, at which time he became the Supreme Duke of Lithuania in exchange for naming his cousin Vytautas as the new Grand Duke. Władysław II initially served as King of Poland alongside his wife Jadwiga until her death in 1399, and then the sole ruler until his own death in 1434.

Raised a Lithuanian polytheist, he converted to Catholicism in 1386 and baptized as Ladislaus (Polish: Władysław) in Kraków, married the young Queen Jadwiga, and was crowned King of Poland as Władysław II Jagiełło. In 1387, he converted Lithuania to Catholicism. His reign in Poland started in 1399, upon the death of Queen Jadwiga, lasted a further thirty-five years, and laid the foundation for the centuries-long Polish–Lithuanian union. He was a member of the Jagiellonian dynasty in Poland that bears his name and was previously also known as the Gediminid dynasty in the Grand Duchy of Lithuania. The dynasty ruled both states until 1572, and became one of the most influential dynasties in late medieval and early modern Europe.

Sigismund II Augustus (Polish: Zygmunt II August, Lithuanian: Žygimantas Augustas; 1 August 1520 – 7 July 1572) was King of Poland and Grand Duke of Lithuania, the son of Sigismund I the Old, whom Sigismund II succeeded in 1548. He was the first ruler of the Polish–Lithuanian Commonwealth and the last male monarch from the Jagiellonian dynasty.

Sigismund was elder of two sons of Italian-born Bona Sforza and Sigismund the Old, and the only one to survive infancy. From the beginning he was groomed and extensively educated as a successor. In 1529 he was chosen as king in vivente rege election while his father was still alive. Sigismund Augustus continued a tolerance policy towards minorities and maintained peaceful relations with neighbouring countries, with the exception of the Northern Seven Years' War which aimed to secure Baltic trade. Under his patronage, culture flourished in Poland; he was a collector of tapestries from the Low Countries and collected military memorabilia as well as swords, armours and jewellery. Sigismund Augustus' rule is widely considered as the apex of the Polish Golden Age; he established the first regular Polish navy and the first regular postal service in Poland, known today as Poczta Polska. In 1569, he oversaw the signing of the Union of Lublin between Poland and the Grand Duchy of Lithuania, which formed the Polish–Lithuanian Commonwealth and introduced an elective monarchy.

Casimir II the Just (Polish: Kazimierz II Sprawiedliwy; 28 October 1138 – 5 May 1194) was Duke of Wiślica in Lesser Poland from 1166 to 1173, and Duke of Sandomierz from 1173 onward. In 1177, he became ruler of the Polish Seniorate Province at Kraków and thereby High Duke of Poland — a position he held until his death, though briefly interrupted by his elder brother and predecessor, Mieszko III.

In 1186, Casimir inherited the Duchy of Masovia from his nephew Leszek, becoming the progenitor of the Masovian branch of the royal Piast dynasty and great-grandfather of the later Polish king Władysław I the Elbow-high. The honorific title "the Just" was not contemporary and first appeared in the 16th century.

Wenceslaus II Přemyslid (Czech: Václav II.; Polish: Wacław II Czeski; 27 September 1271 – 21 June 1305) was King of Bohemia (1278–1305), Duke of Cracow (1291–1305), and King of Poland (1296–1305).

He was the only son of King Ottokar II of Bohemia and Ottokar's second wife Kunigunda. He was born in 1271, ten years after the marriage of his parents. Kunigunda was the daughter of Rostislav Mikhailovich, lord of Slavonia, son of a Grand Prince of Kiev, and Anna of Hungary, daughter of Béla IV of Hungary. His great-grandfather was the German king Philip of Swabia. Wenceslaus II was the grandfather of the Holy Roman Emperor, Charles IV. He was a member of the Přemyslid dynasty.