William I (Willem Frederik; 24 August 1772 – 12 December 1843) was King of the Netherlands and Grand Duke of Luxembourg from 1815 until his abdication in 1840.
Born as the son of William V, Prince of Orange, the last stadtholder of the Dutch Republic, and Wilhelmina of Prussia, William experienced significant political upheavals early in life. He fought against the French invasion during the Flanders campaign, and after the Batavian Revolution in 1795, his family went into exile. He briefly ruled the Principality of Nassau-Orange-Fulda before Napoleon's French troops' occupation forced him out of power. Following the defeat of Napoleon in 1814, William was invited back to the Netherlands, where he proclaimed himself Sovereign Prince of the United Netherlands.