Original: Ã lisabeth was able to leave Spain in 1748 . In the Treaty of Aix-la-Chapelle ( 1748 ) which ended the War of the Austrian Succession , Holy Roman Empress Maria Theresa had to cede the duchies of Parma , Piacenza and Guastalla to her enemy , Philip V of Spain .
Simplified: Louise Ã lisabeth was able to leave Spain in 1748 when her husband was created Duke of Parma thanks to the Treaty of Aix-la-Chapelle ( 1748 ) which ended the War of the Austrian Succession .