Maria Theresa of Austria (13 May 1717 – 29 November 1780) was the only female ruler of the Habsburg dominions and the last of the House of Habsburg. She was the sovereign of Austria, Hungary, Croatia, Bohemia, Mantua, Milan, Lodomeria and Galicia, the Austrian Netherlands, and Parma. By marriage, she was Duchess of Lorraine, Grand Duchess of Tuscany, and Holy Roman Empress.
She started her 40-year reign when her father, Emperor Charles VI, died in October 1740. Charles VI paved the way for her accession with the Pragmatic Sanction of 1713, as the Habsburg lands were bound by Salic law which prevented female succession. Upon the death of her father, Saxony, Prussia, Bavaria and France repudiated the sanction they had recognised during his lifetime. Prussia proceeded to invade the affluent Habsburg province of Silesia, sparking a nine-year conflict known as the War of the Austrian Succession. Maria Theresa would later unsuccessfully try to reconquer Silesia during the Seven Years' War.
She married Francis Stephen of Lorraine and had sixteen children, including Queen Marie Antoinette of France, Queen Maria Carolina of Naples, Duchess Maria Amalia of Parma and two Holy Roman Emperors, Joseph II and Leopold II. Though she was expected to cede power to Francis and Joseph, both of whom were officially her co-rulers in Austria and Bohemia, Maria Theresa was the absolute sovereign who ruled by the counsel of her advisers. She understood the importance of her public persona and was able to simultaneously evoke both esteem and affection from her subjects.
Maria Theresa promulgated financial and educational reforms, promoted commerce and the development of agriculture, and reorganised Austria's ramshackle military, all of which strengthened Austria's international standing.