The three rules known for unifying Japan are Oda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu.
Charles and his wife Elizabeth Christine had not had children, since 1711, Charles had been the sole surviving male member of the House of Habsburg. Charles's older brother, Joseph I, had died without male issue, leaving Joseph's daughter Maria Josepha as the heir presumptive. That presented two problems. First, a prior agreement with his brother, known as the Mutual Pact of Succession, had agreed that in the absence of male heirs, Joseph's daughters would take precedence over Charles's daughters in all Habsburg lands. Though Charles had no children, if he were to be survived by daughters alone, they would be cut out of the inheritance. Secondly, because Salic law precluded female inheritance, Charles VI needed to take extraordinary measures to avoid a protracted succession dispute, as other claimants would have surely contested a female inheritance. Charles VI was definitely succeeded by his own elder daughter, Maria Theresa (born 1717). However, despite the promulgation of the Pragmatic Sanction, her accession in 1740 resulted in the outbreak of the War of the Austrian Succession as Charles-Albert of Bavaria, backed by France, contested her inheritance. After the war, Maria Theresa's inheritance of the Habsburg lands was confirmed by the Treaty of Aix-la-Chapelle, and the election of her husband, Francis I, as Holy Roman Emperor was secured by the Treaty of Füssen.
