She bore her husband Leopold of Anhalt-Dessau the obligatory heir and a spare while he had numerous other children. Her Wikipedia article is here.
This Tischbein portrait of Duchess Luise shows revolutionary French fashion has reached eastern Germany in 1794.
Keywords: 1794, Tischbein, Luise of Brandenburg-Schwedt, Hohenzollern family, Ascania family, Countess, Duchess, German, long straight coiffure, veil, vee neckline, elbow length tight sleeves, waist band, Empire waistline, close skirt, scarf