Queen Maria Theresa of Austria was a significant ruler in the 18th century, reigning from 1740 to 1780. She was the only female ruler of the Habsburg dominions and is known for her strong leadership and reforms. Maria Theresa implemented various changes in education, taxation, and military organization, which helped modernize her empire. Born on May 13, 1717, she was the daughter of Holy Roman Emperor Charles VI. Maria Theresa married Francis I, Holy Roman Emperor, and together they had 16 children, including Marie Antoinette. Her reign marked a pivotal period in European history, influencing politics and culture across the continent.