Sebastian was King of Portugal from 11 June 1557 to 4 August 1578 and the penultimate Portuguese monarch of the House of Aviz.
He was the son of João Manuel, Prince of Portugal, and his wife, Joanna of Austria. He was the grandson of King John III... Wikipedia
Born: January 20, 1554
Died: August 4, 1578 (age 24 years), Ksar el-Kebir, Morocco
Full name: Sebastian
Place of burial: Jerónimos Monastery, Lisbon, Portugal
Deposed date: 1578