She left her mother and sister Maria, who had accompanied her to Swedish Pomerania, and was escorted by baron Taube by sea to Karlskrona in Sweden, where she was welcomed by the king.

Queen Frederica was admired for her beauty but made a bad impression because of her shyness, which caused her to isolate herself and refrain from fulfilling her ceremonial duties, and she disliked society life and representation.

With the exception of her chief lady in waiting, countess Piper, the king had appointed girls of about the same age as herself to be her courtiers, such as Aurora Wilhelmina Koskull, Fredrika von Kaulbars and Emilie De Geer, with whom she reportedly played children's games.

[1] Both being inexperienced, they reportedly had difficulty in connecting sexually, which frustrated the king and caused him to behave with impatient displeasure and suspicion toward her, which worsened the problems because of the shyness of the introverted Frederica.

This did not benefit the marriage from her point of view, as they were not sexually compatible: the king, who had a strong sexual drive but disliked extramarital sex, was sometimes delayed for hours after "having entered the queen's bed chamber" in the morning, so much that the members of the royal council saw themselves obliged to interrupt and ask the king to "spare the queen's health", while Frederica complained in letters to her mother how it tired and exhausted her without giving fulfillment.

[1] The relationship between the king and the queen improved after the birth of their first child in 1799, after which they lived an intimate and harmonious family life in which they grew close through their mutual interest in their children.

In 1800, he had all her young maids of honor relieved from their positions because of their frivolous behavior and replaced with older married ladies-in-waiting,[2] such as Hedvig Amalia Charlotta Klinckowström and Charlotta Aurora De Geer, and six years later, when a frivolous play was performed by a French theater company at the Royal Swedish Opera in the presence of the queen, the king had the French theater company exiled and the Opera closed down.

Frederica amused the king by her skillful clavichord playing, was reportedly joyful in the company of her small circle of friends, especially in the absence of the monarch, and devoted herself to the upbringing of her children.

[1] In 1802, Frederica accompanied her spouse to the province of Finland, during which a meeting was arranged between her and her sisters, the Russian empress Elizabeth and Amalie, in Abborrfors on the border.

[1] She was not allowed to accompany the king when he left for Germany to participate in the War of the Fourth Coalition in November 1805, nor was she appointed to serve in the regency during his absence.

[6] In the winter of 1806–1807, she joined the king in Malmö, where she hosted her sister Princess Marie of Baden, who was a refugee after having fled Napoleon's conquest of the Duchy of Brunswick.

The day after, he was captured at the royal palace in Stockholm in the Coup of 1809, imprisoned at Gripsholm Castle and deposed on 10 May in favor of his uncle, who succeeded him as Charles XIII of Sweden on 6 June.

Her successor, Queen Charlotte, who felt sympathy for her and often visited her, belonged to the Gustavians and wished to preserve the right to the throne for Frederica's son, Gustav.

[9] Her second request was granted her after intervention from queen Charlotte, and Frederica and her children joined Gustav Adolf at Gripsholm Castle after the coronation of the new monarch on 6 June.

During her house arrest at Gripsholm Castle, the question of her son crown prince Gustav's right to the throne was not yet settled and a matter of debate.

These plans were in fact presented to her, but she declined: "The Queen displayed a nobility in her feelings, which makes her worthy of a crown of honor and placed her above the pitiful earthly royalty.

Frederica was offered to be escorted with all honors due to a member of the house of Baden if she traveled alone, but declined and brought no courtier with her, only her German chamber maid Elisabeth Freidlein.

[1] These differences caused Gustav Adolf to leave alone for Basel in Switzerland in April 1810, from which he expressed complaints about their sexual incompatibility and demanded a divorce.

In practice, she spent most of her time in the court of Karlsruhe from 1814 onward, and also traveled a lot around Germany, Switzerland and Italy, using the name Countess Itterburg after a ruin in Hesse, which she had acquired.

[1] In accordance with the abdication terms, she kept her title of queen and had her own court, headed by the Swedish baron O. M. Munck af Fulkila, and kept in close contact with her many relatives and family in Germany.