Maria Theresa of the House of Habsburg was Archduchess of Austria, Queen of Hungary, Queen of Bohemia, Margrave of Moravia et cetera. She was the only ruling woman on the Czech throne. She is often mistaken for an empress, but she was only the wife of Francis I Stephen of Lorraine, who was elected Holy Roman Emperor. Their marriage produced 16 children, 12 of whom lived to adulthood and four of whom were boys. She took over the government at the age of twenty-three, and although she did not receive any political education, she ranked among the successful monarchs in history. However, she had to fight for her place. Between 1740 and 1763, wars for the succession to the Habsburg throne took place between Maria Theresa and her neighbours Prussia and Bavaria, with the support of France. The main reason was the neighbour’s rejection of a decree that guaranteed Maria Theresa the rights of heir to the throne. From this, in addition to the dynastic claim of Maximilian of Bavaria, the false claims of the Prussian king Frederick II to the Silesian territories arose. The third and the biggest conflict entered history as the Seven Years’ War. Maria Theresa went down in history with many reforms, which included the introduction of compulsory schooling, permanent surnames or the unification of weights and measures, military reform, modernization of regional administration, and the creation of a new postal code. These steps greatly contributed to the modernization of the empire and influenced the lives of the inhabitants for centuries to come.