On August 7, 1775 Marie Louise married Jean-Baptiste-Pierre Le Brun, a well known painter and art dealer. As Le Brun’s career began to flourish, she was requested to paint portraits of many of the nobility of the day. She was even invited to the Palace of Versailles to paint Marie Antoinette. Supremely elated by the result of her first portrait, Queen Antoinette hired Marie Louise for the next six years, creating a collection of over 30 portraits of the Queen and her family. Then, finally on 12 February 1780, Le Brun and her husband were overjoyed when her daughter, Jeanne Julie Louise finally made her debut. After the devastating arrest of the royal family during the French Revolution, Le Brun fled France with Julie. They became very migratory, as traveling from spot to spot became a habit. Their travels included Russia, Italy, and Austria which contributed to the increase of her gift. While in Saint Petersburg, Le Brun was selected to become a member of the Academy of Fine Arts of Saint Petersburg. Just a short time later, her daughter, Julie married a Russian nobleman.
After a long tedious campaign on her behalf led by her ex husband and other family members to have her name removed from the record of counter revolutionary émigrés, Marie Louise was finally able to return to France under the rein of Napoleon I. Beginning in the start of the 19th century, she visited Europe painting the portrait of several British nobles including Lord Byron. In 1807, she ventured to Switzerland and was made an honorary member of the Société pour l'Avancement des Beaux-Arts of Geneva. She published two memoirs in 1835 & 1837 which were staples that provided a dynamic account of her life and times. Marie Louise stayed in Paris until her death on March 30, 1842 at which point her body was taken back to Louveciennes and buried in the Cimetière de Louveciennes near her old home. Engraved on her tombstone is, "Ici, enfin, je repose, which means" Here, at last, I rest”. Le Brun left a legacy of 660 portraits and over 200 landscapes not including her private collections. Her works of art may be found at major museums, such as Hermitage Museum, London's National Gallery, in Europe as well as the United States.