Augustus III (Polish: August III, Lithuanian: Augustas III; 17 October 1696 – 5 October 1763) was King of Poland and Grand Duke of Lithuania from 1734 until 1763, as well as Elector of Saxony in the Holy Roman Empire from 1733 until 1763 where he was known as Frederick Augustus II (German: Friedrich August II).
The only legitimate son of Augustus II of Poland, he followed his father’s example by joining the Roman Catholic Church in 1712. In 1719 he married Maria Josepha, daughter of the Holy Roman emperor Joseph I and became elector of Saxony on his father’s death in 1733. As a candidate for the Polish crown, he secured the support of the emperor Charles VI by assenting to the Pragmatic Sanction of 1713, designed to preserve the integrity of the Habsburg inheritance, and that of the Russian empress Anna by supporting Russia’s claim to Courland. Chosen king by a small minority of electors on October 5, 1733, he drove his rival, the former Polish king Stanisław I, into exile. He was crowned in Kraków on January 17, 1734, and was generally recognised as king in Warsaw in June 1736.
Augustus gave Saxon support to Austria against Prussia in the War of the Austrian Succession (1742) and again in the Seven Years’ War (1756). His last years were marked by the increasing influence of the Czartoryski and Poniatowski families, and by the intervention of Catherine the Great in Polish affairs. His rule deepened the anarchism in Poland and increased the country’s dependence on its neighbours. The Russian Empire, which had assisted him in his bid to succeed his father, prevented him from installing his family on the Polish throne, supporting instead the aristocrat Stanisław August Poniatowski. During his reign, Augustus spent little time in Poland and more interested in ease and pleasure than in affairs of state, this notable patron of the arts left the administration of Saxony and Poland to his chief adviser, Heinrich von Brühl, who in turn left Polish administration chiefly to the powerful Czartoryski family.
The reign of Augustus witnessed one of the greatest periods of disorder within Poland.