Title: John Sigismund, Elector of Brandenburg
Content:  John Sigismund was born in Halle an der Saale to Joachim III Frederick, Elector of Brandenburg, and his first wife Catherine of Brandenburg-Küstrin. He succeeded his father as Margrave of Brandenburg in 1608. In 1611, John Sigismund traveled from Königsberg to Warsaw, where on 16 November 1611 he gave feudal homage to Sigismund III Vasa, King of Poland (the Duchy of Prussia was a Polish fief at the time). He officially became Duke of Prussia in 1618, although he had served as regent on behalf of the mentally-disturbed Albert Frederick, Duke of Prussia, for several years prior. He suffered a stroke in 1616 from which he didn't recover and died in 1619. John Sigismund gave the Reichshof Castrop to his teacher and educator Carl Friedrich von Bordelius, whereas he received the territories of Cleves, Mark, and Ravensberg in the Treaty of Xanten in 1614.
Title: Sigismund, Holy Roman Emperor
Content:  entirely devoted to his adopted country. King Louis named him as his heir and appointed him his successor as King of Hungary. In 1381, the then 13-year-old Sigismund was sent to Kraków by his eldest half-brother and guardian Wenceslaus, King of Germany and Bohemia, to learn Polish and to become acquainted with the land and its people. King Wenceslaus also gave him Neumark to facilitate communication between Brandenburg and Poland. The disagreement between Polish landlords of Lesser Poland on one side and landlords of Greater Poland on the other, regarding the choice of the future King of Poland, finally ended in choosing the Lithuanian side. The support of the lords of Greater Poland was however not enough to give Prince Sigismund the Polish crown. Instead, the landlords of Lesser Poland gave it to Mary's younger sister Jadwiga I of Poland, who married Jogaila of Lithuania.
Title: John Sigismund, Elector of Brandenburg
Content:  John Sigismund (Johann Sigismund; 8 November 1572 – 23 December 1619) was a Prince-elector of the Margraviate of Brandenburg from the House of Hohenzollern. He became the Duke of Prussia through his marriage to Duchess Anna, the eldest daughter of Duke Albert Frederick of Prussia who died without sons. Their marriage resulted in the potential creation of Brandenburg-Prussia, which became a reality after Poland's leader appointed John Sigismund in charge of Prussia in regency and, shortly thereafter, Albert Frederick died without an able, direct male heir.
Title: Polish Golden Age
Content:   After the death of John III of Sweden, his son Sigismund became heir to the throne of Sweden. Sigismund at that time was already King of Poland (since 1587). Sigismund certainly valued the Swedish throne and upon learning about the death of his father, and the pretensions to the throne of his uncle, Duke Charles of Södermanland, he asked the Sejm (Polish parliament) for permission to leave the Commonwealth and go to Sweden, where he could temporarily secure the Swedish crown. The Sejm gave him permission, and on 3 August 1593, Sigismund, accompanied by his wife, Anna of Habsburg, and other followers, 
Title: Polish Golden Age
Content:  John III of Sweden married Catherine Jagellonka, the sister of Sigismund II Augustus of Poland. When Sigismund II of Poland died without issue, the son of John III of Sweden and Catherine Jagellonka was elected King of Poland and Grand Duke of Lithuania as Sigismund III in 1587. On John's death, Sigismund also gained the Swedish throne.
Title: Sigismund I the Old
Content:  The son of King Casimir IV Jagiellon and Elisabeth Habsburg of Austria, Sigismund followed his brothers John Albert and Alexander to the Polish throne. Their eldest brother Vladislaus became king of Bohemia, Hungary, and Croatia. Sigismund was christened as the namesake of his Habsburg maternal great-grandfather, Holy Roman Emperor Sigismund. When Casimir died in 1492, Sigismund was his only son without any titles or land. From 1495 to 1496, he petitioned his brother Alexander to provide him with land, and Elisabeth Habsburg attempted to install him on the Austrian throne. Both efforts failed. In 1497, King John I Albert, his older brother, led an invasion of Moldavia that was intended to place Sigismund on its throne. This, too, was a disastrous failure. Finally, his eldest brother 
Title: Sigismund II Augustus
Content:  Sigismund II Augustus (Zygmunt II August, 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 the only son of Italian-born Bona Sforza and Sigismund the Old. From the beginning he was groomed and extensively educated as a successor. In 1529 he was crowned vivente rege while his father was still alive. Sigismund Augustus continued a tolerance policy towards minorities and maintained peaceful relations with neighbouring countries, with the exception 
Title: Sigismund III Vasa
Content:  to Warsaw. Sigismund was the son of John III of Sweden and his first wife, Catherine Jagiellon, daughter of King Sigismund I of Poland. Elected monarch of the Polish–Lithuanian Commonwealth in 1587, he sought to unify Poland and Sweden under one Catholic kingdom, and when he succeeded his deceased father in 1592 the Polish–Swedish union was created. Opposition in Protestant Sweden caused a war against Sigismund headed by Sigismund's uncle Charles IX, who deposed him in 1599. Sigismund attempted to hold absolute power in all his dominions and frequently undermined parliament. He suppressed internal opposition, strengthened Catholic influence and granted privileges to 
Title: Polish–Swedish union
Content:  After the death of John III of Sweden, his son Sigismund became heir to the throne of Sweden. Sigismund at that time was already the elected King of Poland (since 1587). Sigismund certainly valued the Swedish throne and upon learning about the death of his father, and the pretensions to the throne of his uncle, Duke Charles of Södermanland, he asked the Sejm (Polish parliament) for permission to leave the Commonwealth and go to Sweden, where he could secure the Swedish crown. The Sejm gave him permission, and on 3 August 1593, Sigismund, accompanied by his wife, Anna of Habsburg, and other followers, departed for Sweden. In Sweden, he encountered a serious problem due to his religion, as Sigismund was a devoted Catholic, and most of the Swedish population (including Charles) had converted to Lutheranism. There were fears that Sigismund, if elected 
Title: Sigismund I the Old
Content:  Sigismund I the Old (Zygmunt I Stary, Žygimantas II Senasis; 1 January 1467 – 1 April 1548) was King of Poland and Grand Duke of Lithuania from 1506 until his death in 1548. Sigismund I was a member of the Jagiellonian dynasty, the son of Casimir IV and younger brother of Kings John I Albert and Alexander I Jagiellon. He was nicknamed "the Old" in later historiography to distinguish him from his son and successor, Sigismund II Augustus. Sigismund was born in the town of Kozienice in 1467 as the fifth son of Casimir IV and his wife Elizabeth of Austria. He was one of thirteen children 

Question: Who is the father of John Sigismund, Crown Prince of Poland?
Answer: John II Casimir Vasa.