
Twice Polish king, father-in-law of Louis XV.
Stanislaw I Leszczynski was elected King of Poland by a confederation of nobles supported by Sweden's Charles XII during the Great Northern War. His election was contested by Augustus II, leading to a civil war and Swedish intervention.
After Sweden's defeat at the Battle of Poltava, Stanislaw I lost Swedish support and was forced to abdicate the Polish throne. Augustus II was restored as king, and Stanislaw went into exile.
Stanislaw I's daughter, Marie Leszczynska, married King Louis XV of France. This marriage elevated Stanislaw's status and provided him with a French pension and the Duchy of Lorraine as a compensation for losing the Polish throne.
Following the death of Augustus II, Stanislaw I was elected King of Poland for a second time. This election sparked the War of the Polish Succession, as Russia and Austria supported a rival candidate, Augustus III.
After the War of the Polish Succession ended, Stanislaw I formally abdicated the Polish throne. He was granted the Duchy of Lorraine and Bar as a lifetime fief, where he ruled until his death.
Stanislaw I became Duke of Lorraine and Bar, ruling the territories until his death. He implemented administrative reforms, supported the arts, and founded the Stanislas Library and the Royal Society of Sciences and Letters in Nancy.