Duke John IV, also known as John IV of Portugal, was a significant figure in Portuguese history, ruling from 1640 to 1656. He was the first Duke of Braganza to ascend the throne after the Portuguese Restoration War, which ended the Iberian Union with Spain. His reign marked a period of renewed independence for Portugal and efforts to restore its economy and influence. During his rule, John IV focused on strengthening the monarchy and promoting the arts and culture. He was a patron of the famous composer Heitor Villa-Lobos and supported the development of Portuguese literature. His leadership helped solidify the identity of Portugal as a sovereign nation.