They were raised together at court and was reportedly mutually in love with each other, and there where rumors that they met each other in secret in the home of Brahe's sister Ebba Sparre.
In 1589, he formally asked Sigismund for Anna's hand, and while he was not given a clear answer, he was not refused, which made him hope that he might be accepted.
[2] The attempts of marriage between Princess Anna and Gustaf Brahe was often mentioned but ultimately never brought to fruition, and both remained unmarried.
The potential marriage between princess Anna and Gustaf Brahe was fiercely opposed by Duke Charles, who viewed it as a plot of Gustav Brahe to make princess Anna ruling queen regnant of Sweden while her only brother Sigismund was absent in Poland, and he therefore used their relationship in his libelous chronicle Karlskrönikan.
[3] In 1593, he was appointed the representative of Sigismund III Vasa in Sweden, and was to assist his brother Erik Brahe (1552–1614) as governor of Stockholm.