A genealogical sketch of her is here. The sketch is incomplete because she had a a daughter. The Tassis family, originating from near Bergamo in Lombardia (Lombardy) created the Holy Roman Empire's postal system, the world's first. After limited use, it opened to the public in 1506. They became the Thurn und Taxis family in 1650, starting as Barons, then being elevated to Counts, and finally Princes. The daughter, Maraia Anna van Berchem, can be seen here.
Upgrade image posted 1 February 2014 from Wikimedia. The next four images are out takes from this one.
Marie Louise's basque bodice protrudes showing how it is separate from the skirt while her coat is plainly visible.
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