António Vieira (1608-1697) was a Portuguese Jesuit priest, writer, diplomat, and one of the most influential orators of his time. He was born in Lisbon and spent much of his life in Brazil, where he dedicated himself to evangelization and the defense of indigenous peoples' rights against slavery. He was an advisor to King John IV of Portugal and a prominent figure at court. He is known for his eloquent sermons, letters, and prophetic works.