Facts and Events
Sebastian I (Portuguese: Sebastião I ; 20 January 1554 – 4 August 1578) was King of Portugal and the Algarves from 11 June 1557 to 4 August 1578 and the penultimate Portuguese monarch of the House of Aviz.
He was the son of John Manuel, Prince of Portugal, and his wife, Joanna of Austria. He was the grandson of King John III of Portugal and Holy Roman Emperor Charles V. He disappeared (was presumably killed in action) in the battle of Alcácer Quibir. Sebastian I is often referred to as The Desired (Portuguese: o Desejado), for the Portuguese people longed for his return, to end the decline of Portugal that had occurred because of his death.