Gunilla Bielke; Swedish: Gunilla Johansdotter Bielke af Åkerö was Queen of Sweden as the second wife of King John III. Queen Gunilla is acknowledged to have acted as the political adviser to John III and to have influenced his religious policies in favour of Protestantism.

Sigismund III Vasa was King of Poland and Grand Duke of Lithuania from 1587 to 1632 and, as Sigismund, King of Sweden and Grand Duke of Finland from 1592 to 1599. He was the first Polish sovereign from the House of Vasa. Religiously zealous, he imposed Roman Catholicism across the vast realm, and his crusades against neighbouring states marked Poland's largest territorial expansion. As an enlightened despot, he presided over an era of prosperity and achievement, further distinguished by the transfer of the country's capital from Kraków to Warsaw.