Began co-regency with Joseph II after Francis I's death on August 18, 1765.
On August 18, 1765, the sudden death of her husband, Francis I, in Innsbruck thrust Maria Theresa into a new period of governance as she assumed co-regency with her son Joseph II, who became the Holy Roman Emperor. This transition reflected the evolving structure of imperial governance, balancing Maria Theresa’s experienced and cautious rule with Joseph’s youthful and progressive ideas influenced by the Enlightenment. Despite differing views, their cooperation marked a critical era of reform in administration, military, and legal frameworks within the Habsburg dynasty, steering the empire towards modernization.