Empress Maria Theresa was the only female ruler of the Habsburg Empire, reigning from 1740 to 1780. She was born on May 13, 1717, and became the archduchess of Austria and queen of Hungary and Bohemia. Her reign was marked by significant reforms in administration, education, and military organization, which strengthened her empire. Maria Theresa faced numerous challenges, including the War of the Austrian Succession and the Seven Years' War. Despite these conflicts, she successfully maintained her family's power and implemented policies that improved the lives of her subjects, leaving a lasting legacy in European history.