This work is about the genius named both Miguel de Villanueva and Michael Servetus - polymath, first european to describe Pulmonary circulation, defender of Tolerance, theologian and the only individual in history burnt at a stake by both Catholics and Protestants. There was not a single document about him before 1531, when he was already living in Basel (Germany). This book provides the first documents of Michael Servetus in Spain (13 new documents), and with these and other new documentation it attempts to reconstruct his youth and childhood years, in order to understand how his unique mind and personality were forged. The book is divided in two independent parts: The central part of the book is the most important, for it has the very documents of Servetus, indisputably. It starts by studying the marriage and family Serveto-Conesa who lived in Villanueva de Sigena, where Michael Servetus lived. The book corrects many errors concerning the genealogy of the wife's family, the number of children they had (not 2 but 7), their in-laws, their uncles, aunts and cousins, friends and business partners. It goes on to describe Michael Servetus's primary education in the nearby village of Sariñena, and his teacher at that Studium. The next chapter deals with the issue of Juan Quintana, Confessor of the Emperor and Michael Servetus's supposed mentor, and reveals this previously unknown cleric's family and origin. Preparing the ground for the main chapters, it studies the figure of master Gaspar Lax, who will become the High Master of Zaragoza Studium Generale of Arts. This primitive University of Zaragoza is deeply studied with many new documents, describing its mechanisms, appointments, hierarchy, privileges, salaries, taught subjects, rooms, and title acquisitions, and pays special attention to the figure of the four Masters of Arts, who were similar to professors in Arts. After having prepared the reader, the new documents of Servetus are presented, and the chapter deals course by course from 1520/1521 to 1526/1527 with the life at this University, its teachers, pupils and events. And it is at this moment when one can see for the first time Michael Servetus's life and evolution from student to one of the four Masters of Arts in the University. In this last section, the book's special focus is Michael Servetus's reason to have to leave Spain: he had a serious brawl with his relative Gaspar Lax, High Master, Vice chancellor and Rector of the University, a very influential man in the academic world, and this turned the Sigena family and the Spanish Universities against Michael Servetus, and so he had to leave to Toulouse's University. The last chapter of this central part the book studies erasmism in Zaragoza, -for Servetus was an erasmian- and reveals two unknown circles of erasmians in this city. The beginning and the end of the book - the other part - defend the notion that Michael Servetus alias Revés is actually a child we documented that was born in the proximity of the Tudela town in 1506, with a genital defect, son of Jewish converso parents to the De Villanueva name, and that he was later adopted by the family of Villanueva de Sigena, when his real parents were pursued by the Inquisition in 1515. In order to do that, all the leads shared by both individuals are presented for readers to judge by themselves, from same age, same genital defect, same defenders, same family name, common contacts in both areas, common connections with Lyon printer Gaspar Trechsel, and others.