John IV (, ; 19 March 1604 – 6 November 1656), nicknamed John the Restorer (), was the King of Portugal whose reign, lasting from 1640 until his death, began the Portuguese restoration of independence from Habsburg Spanish rule. His accession established the House of Braganza on the Portuguese throne, and marked the end of the 60-year-old Iberian Union, by which Portugal and Spain shared the same monarch.