The Spanish religious philosopher Michael Servetus (ca. 1511-1553), often called the first Unitarian, denied the divinity of Christ and the doctrine of the Trinity. His views made him abhorrent to both Catholics and Protestants.

Michael Servetus was born at Villanueva. The son of a notary, he became a law student in Toulouse, where he developed an avid interest in the Bible. A Franciscan named Juan de Quintana befriended him in 1525. Quintana became confessor to Emperor Charles V in 1530, and that year Servetus accompanied Quintana to Bologna for Charles's coronation. There the pomp surrounding the Pope repelled him and tended to alienate him from the Roman Catholic Church. This journey was decisive in shaping Servetus's thought, for he also visited Augsburg, where he came into immediate contact with Protestantism, which impressed him favorably. He soon became acquainted with the leading spirit of Rhenish Protestantism, Martin Bucer.

Servetus then published...