She enlisted in the army dressed as a man under the name Petter Hagberg in search for her husband, because she had heard nothing of him since the beginning of the war.
A maid from Färnebo in Västmanland, Anna Maria Engsten, the maid Major P. H. Scharff, distinguished herself at the same occasion in 1790; when the ship she travelled on was evacuated, she refused and stayed on, and singlehandedly steered the ship back to Sweden at night during Russian fire, for which King Gustav III gave her a pension and decorated her with the medal För tapperhet till sjöss for bravery.
After the war, Hagberg was given a månglerska-permit to trade in food in 1793, and she had a spot reserved for her at the square of Oxtorget in Stockholm (1802), which was renewed the last time in 1819.
Here, it was said that; "For about thirty years ago, on the Oxtorget square in Stockholm, one could see an old woman selling ginger-bread cookies on a stand with a medal of bravery on her chest.
She had been married to a guardsman by the name of - if this is correct - Hagström, and found a life filled with loneliness after her husband had been called out to serve at the war of 1788.
In 1828, the life of Brita Hagberg was celebrated in the poem Fruktmånglerskan med Tapperhetsmedalj (The fruit seller woman with a medal of bravery) by the female poet Euphrosyne, (Julia Nyberg) who tells the tale of the female soldier, who dresses herself as a man and enlists in the army in search of her husband.