Hedvig Ulrika Taube (31 October 1714 – 11 February 1744), also Countess von Hessenstein, was a Swedish courtier and countess, a countess of the Holy Roman Empire, and royal mistress to king Frederick I of Sweden from 1731 to 1744. She and Sophie Hagman are the only two official royal mistresses in Swedish history.

Hedvig Taube was one of nine children of Count Edvard Didrik Taube (1681–1751) and Christina Maria Falkenberg (1686–1753). Her sister, Catherine Charlotte, was to marry the brother of scientist Countess Eva Ekeblad, who was also the aunt of the renowned Axel von Fersen the Younger. In 1716, the future king Frederick became one of the godparents to her sister Christina Beata. During the 1720s, her father was nearly ruined and placed in heavy debt because of gambling and bad business: in 1730, the family had been forced to change their city residence to a cheaper one.

Hedvig Taube was described as a beauty, and in 1730, the king noticed her, likely on a visit to baron Otto Reinhold Strömfelt, who was married to her paternal aunt. He started to court her with baskets of fruit and flowers sent to the home of her indebted father: reportedly, jewels and other valuable items were hidden beneath the fruit. He also inquired whether Arvid Horn would be willing to house her, so as to make it possible for the king to court her in person. Horn refused, and during the Riksdag of 1731, he warned the king that he was the topic of dislike in the Clergy estate for courting a young unmarried lady.

The king's favorite and confidant, Erland Broman, convinced her father to agree to a sexual relationship between his daughter and the king. Hedvig Taube herself, however, was engaged to a young count Erik Sparre and refused, supported by her mother. Her mother suggested to take Hedvig Taube with her to their country estate Kungshatt to avoid the king's attention, but her spouse: "sold his daughter to the king for quite a sizable sum. His debts were paid and promotions made for his sons and his relations", and he sent his wife alone to the country and kept his daughter with him in the capital. Her betrothed, Erik Sparre, was also removed, as he was included to be a part of the entourage accompanied the king to his visit to Hesse, and several people were sent to Hedvig Taube to convince her to agree to the king's advances upon his return, notably her father's maiden aunt Beata Taube and Carl Tersmeden, calling her future fate more beautiful than she could imagine. She was convinced by being pressed by her duty to her family, and the custom of maîtresse-en-titre in France, which was not seen as improper there and would be introduced in Sweden with her. Meanwhile, her mother was convinced to agree to the matter by Eleonora Lindhielm and Hedvig Catharina Lillie, married to Daniel Niklas von Höpken and Magnus Julius De la Gardie, who wished to benefit their political careers by supporting the king.

In the company of her mother and aunt, Hedvig Taube was brought to the king at Karlberg Palace upon his return from Hesse 12 November 1731. Shortly thereafter, she was appointed hovfröken (maid of honour), to queen Ulrika Eleonora to become accessible to the king at court and, though it was not spoken aloud, to become his mistress. When the carriage came to take her to court, Tersmeden reported her saying; My fate is harder than I could imagine. I am being forced to expose my virtue to save a family ruined by gambling. Her father was appointed riksråd, and others who had participated in the affair in the king's favor were rewarded.

During her tenure as maid of honor at court, her position as mistress to the king was kept secret. Initially, the relationship was kept a secret from the queen by her favorite and confidant Emerentia von Düben. The queen did not consider it proper to expose the monarch to slander in public, and participated in protecting the king's reputation. During the hunting trip to Dalarna, which the royal court undertook in 1732 to celebrate the visit of the king's brother Prince William of Hesse, the queen demonstrated her disregard to the rumors by displaying affection to her maid of honor Hedvig Taube, when they were seen by the public during walks.

At this point, she was regarded at court as a temporary amusement. She was referred to as la belle Colombe by the king, who gave her gifts financed by his income from Hesse. In the winter of 1733–34, Taube was pregnant with her first child. The affair was kept a secret: Taube retired to her room simulating bedridden illness as soon as the pregnancy could not be hidden, and before the birth was due, in February 1734 the king convinced the queen to take the royal court to Ulriksdal Palace, and Taube was left alone to give birth in the royal palace in Stockholm. The child, a daughter known as "Mamsell Erlich", was left to a foster mother, but died soon after. Hedvig Taube avoided official discovery, but the birth was subject of widespread gossip in the capital.

Hedvig Taube was supported by her family, as well as the politicians Daniel Niklas von Höpken, Karl Gyllenborg and Hans Reinhold von Fersen and their followers, and on their request, she made recommendations of candidates to political offices to the king, something which created rising discontent. She did, however, not display any personal interest in state affairs. The French envoy in Sweden, Charles Louis de Biaudos de Casteja, was known to recognize the participation of women in the Swedish party strife of the Age of Liberty and confirmed to have recruited several female agents for French interests in Sweden, such as Charlotta von Liewen and Margareta Gyllenstierna, attempted to recruit the king's mistress Hedvig Taube for 100.000 livres, but she refused and expressed no interest to be involved in state affairs.