Aurora Wilhelmina Koskull was the daughter of the courtier Baron Otto Anders Koskull and Amalia Beata Silfversparre.
Court service
In 1797, Koskull became one of the first hovfröken appointed to the new queen, Frederica of Baden. In 1800, the queen's maids-of-honor were dismissed by the king because of many scandals involving their love affairs, and replaced with statsfru. Impoverished, Koskull moved in with her aunt, Ulrika Katarina Koskull, and her aunt's wealthy husband, Count Magnus Fredrik Brahe. The queen's former maids-of-honor were all compensated with the formal position as maids-of-honor to the household of the infant crown prince, while he was still small enough to have female courtiers, and as such she still had the right to attend court, and often participated in high society life. In 1802, Koskull is noted as an accomplished singer in the performances staged by the amateur theatre society of Princess Charlotte at Rosersberg Palace. During the visit of Prince William Frederick in Stockholm during the winter of 1802–03, there were rumours of an affair between them, which was mentioned in the diary of Princess Charlotte: Being without a dowry, it was difficult for Koskull to marry. In 1806, half a year after the death of her aunt, she married her aunt's rich widower, Count Brahe. She had two children, Ulrika Vilhelmina Brahe and Magnus Brahe.
In 1811, her spouse was appointed Swedish minister to France, and she accompanied him to Paris. In France, she attracted the attention of Napoleon, who called her la belle suédoise. During the reign of Charles XIII and Charles XIV John she had a powerful position, being related to the influential royal mistressMariana Koskull as well as being the stepmother of the royal favorite and politician Magnus Brahe, who felt great affection for her, and reportedly asked her for advice in matters of state. In 1810, she attracted the attention of the elected Crown PrinceJean-Baptiste Bernadotte, the futureCharles XIV John of Sweden who was reportedly in love with her and courted her. There were rumours of an affair between them, but these are not regarded to be true, and instead Charles John was reportedly rejected by her and instead entered in to a relationship with her relative, Mariana Koskull. In June 1815, the matter was mentioned in the famous journal of queen Charlotte: Not soon after, there was a rumour that Brahe had supplanted her cousin Koskull as the lover of the crown prince: In June 1817, queen Charlotte summarized the difference of the crown prince's relationship toward the two cousins, while also giving Brahe a personal description:
In 1823, she was offered the position of head lady-in-waiting to the new crown princess, Josephine of Leuchtenberg, upon her arrival to Sweden, being at that time one of the leading women of court life and high society; she refused and the office was instead given to Elisabet Charlotta Piper, but she did accept to have the position temporary, by meeting Josephine in Germany and escorting her the last part of the journey to Sweden: Brahe was a leading figure of the aristocratic life of Stockholm, a position she kept after having been a widowed in 1826. She had a very good relationship to her stepson Magnus Brahe, who discussed state affairs with her and asked her for political advice. It was said that she "took the lead in the most notable salon of the Swedish aristocracy with noble dignity" and her salon was described as "a school, where youth took their knowledge in the art of good mannered socializing"; also in her old age, she was said to keep a "beautiful and majestic appearance".
