Hortense was born in Paris, France, to Josephine Tascher de la Pagerie and Alexandre, Vicomte de Beauharnais. After her father's execution during the Reign of Terror, her mother married Napoleon Bonaparte.
At Napoleon's request, Hortense married his brother Louis Bonaparte. Napoleon appointed the couple King and Queen of Holland. Although three sons were born to the marriage (one of them the future Napoleon III), it was an unhappy one (the identity of at least one of the children's fathers is open to debate), and they separated in 1810.
Despite the dissolution of his marriage to her mother, and the bad state of Hortense's marriage to Louis, Hortense supported Napoleon after his return from exile on Elba in 1815. This led to her banishment from France after his final defeat. After travelling in Germany and Italy, Hortense bought the Château of Arenenberg in the Swiss canton of Thurgau, where she lived until her death on October 5, 1837.