Michael Servetus is a historical character mentioned in Uncharted: Golden Abyss, as part of the 'Sete Cidades' mystery. Servetus is not his actual name, that was Michael de Villenueva. He is known as Servetus as that is the pseudonym he used when writing books which were judged to be heretical by the Catholic Church.
Michael was born in Navarre, Spain on 29th September 1511, and early in his life showed a talent for languages. He may have studied Latin, Greek and Hebrew under the tuition of Dominican friars, and at age fifteen he entered service as a Franciscan friar. He read the entirety of the Bible in its original languages, where manuscripts were available. In 1526, he attended the University of Toulouse to study law, where he was suspected of participating in secret meetings and activities with Protestant students.
In 1528, Michael began secretly contacting Protestants, using the pseudonym 'Servetus'. He published several books under this name, including 'On the Errors of the Trinity', 'Dialogues on the Trinity' and 'On the Justice of Christ's Reign'. In 1536, he taught astrology and mathematics while studying medicine at the University of Paris. After envious teachers tried to have him removed, he moved to Montpelier to finish his studies in 1539, and decided to publish future books anonymously.
Michael practiced medicine near Lyon for fifteen years, before his book Christianismi Restituto brought him into direct conflict with the Catholic Church. The book, which rejected ideas of predestination and questioned the validity of the Holy Trinity and infant baptism, was taken by the bishop of Geneva, Calvin, as a personal attack on his theology.
In 1553, a merchant denounced Michael as a heretic, and was arrested and imprisoned by the Church in Vienne in April. Michael escaped from prison three days later, but was arrested again in Geneva. He was tried and found guilty of heresy, and was burned at the stake on 27 October 1553.
At some point in his life, although exactly when is unknown, Michael encountered the Sete Cidades and the legend of the Seven Cities of Gold. By the time of his death, he was a high-ranking member of the order, the suppression of which may have had something to do with his execution.