Margareta Alströmer was born the child of the baron, statesman and amateur musician Patrick Alströmer and Christina Maria Ollonberg, and the granddaughter of Jonas Alströmer. Her father had made their home a center of the cultural life in the city of Gothenburg and was known as the founder of the theatre Comediehuset (1779).
She was raised in a very cultural environment. She was also a popular dilettante singer at private concerts and public charity concerts, and in the same year, she was elected to the Academy of Music, a first for her combined sex and status. Previously, only women who were professional artists had been elected, such as Elisabeth Olin in 1782, but in 1795, Alströmer was elected with Christina Fredenheim (1762–1841) and Anna Brita Wendelius (1741–1804), followed in 1801 by the siblings Sophia (1773–1858) and Emilie (1780–1863) Brandel, Ulrica Bouck and Marie Antoinette Petersén (1771–1855), all dilettantes.
In the Academy of Arts, Wendela Gustafva Sparre (1772–1855), another noble dilettante artist, was elected in to the academy in 1797.
In 1799, Alströmer participated in a concert in Stockholm playing the Clavichord to the singing of Christoffer Christian Karsten, Marianne Ehrenström and Christina Fredenheim.
Royal Swedish Academy of Fine Arts]
She was a member of the Royal Swedish Academy of Arts and of the Royal Swedish Academy of Music. Alströmer was described as a "skillful dilettante in the art of painting" and was elected as a member of the Academy of Arts by a large majority in 1795.
