In 1630, her mother and four of her five siblings were killed when imperial troops stormed Calbe; only Anna Margareta was able to escape, finding shelter in the Cistercian convent in Egeln.
In 1636, Anna Margareta became a ward of the German countess Elisabeth Juliane of Erbach, who married the Swedish commander Johan Banér that year.
Anna Margareta met Carl Gustaf Wrangel in a Swedish military camp; they became engaged in May 1640 and married for love on 1 June in Saalfeld.
The marriage was controversial because Carl Gustaf was a member of the powerful Wrangel family, who thought that his relationship with an untitled and poor German noblewoman was inappropriate, but the criticism of his peers did not bother him much.
After the Thirty Years' War, they lived mainly at the Wrangel estates in Swedish Pomerania, where Anna Margareta died.