as heiress to four duchies, modena and reggio from her father and massa and carrara from her mother, she was a very attractive candidate for marriage. from 1753 it was arranaged that she would marry archduke leopold of austria, younger son of empress maria theresa. the situation changed when leopold's childlessness made leopold the heir to the holy roman empire. as a result, she was instead engaged to leopold's brother, archduke ferdinand of austria. plans began in 1754 and it was concluded by their actual marriage in milan on 15 october 1771. some of the festivities for the marriage were played by mozart.