Afonso VI was the King of Portugal from 1656 to 1683. He became king at a young age after the death of his father, John IV. His reign was marked by political instability and conflicts, including the Portuguese Restoration War against Spain. Afonso VI struggled with health issues, which affected his ability to govern effectively. In 1667, Afonso VI was declared incapable of ruling due to his mental health problems. His brother, Peter II, took over as regent and later became king. Afonso VI's reign is often remembered for the challenges faced by Portugal during a tumultuous period in its history.