Maria Theresa was Archduchess of Austria, the first and only female ruler of Austria for the 650 years of Austrian history. She was the daughter of Charles II, Holy Roman Emperor, whose only son died in 1716 when he was just a baby. Maria Theresa, being a woman, could not succeed to the imperial throne of the Holy Roman Empire, but she succeeded to the royal thrones of Croatia, Dalmatia and Bohemia. She eventually became Holy Roman Empress, when she married Francis I, her father's succesor. She was the de facto ruler of the Holy Roman Empire. Francis I and Maria Theresa had 16 children - their 15th child and youngest daughter was the famous Marie Antoinette.