Gustav IV Adolf of Sweden is deposed in the Coup of 1809.

Gustav IV Adolf or Gustav IV Adolph was King of Sweden from 1792 until he was deposed in a coup in 1809. He was also the last Swedish monarch to be the ruler of Finland.

The Coup of 1809, also referred to as the Revolution of 1809, was a Swedish coup d'état on 13 March of that year by a group of noblemen led by Georg Adlersparre, with support from the Western Army. The coup resulted in the deposition of King Gustav IV Adolf and the introduction of a new Instrument of Government. The coup was provoked by the disastrous Finnish War. The leaders of the coup are known in history collectively as 1809 års män.

March 13 is the 72nd day of the year in the Gregorian calendar; 293 days remain until the end of the year.