Peninsula from the Moors in 1492, had been preoccupied with converting the Muslim and Jewish populations of the newly conquered regions through the establishment of the Spanish Inquisition in 1478. The rulers of the nation stressed political, cultural, and religious unity, and by the time of the Lutheran Reformation, the Spanish Inquisition was already 40 years old and had the capability of quickly persecuting any new movement that the leaders of the Catholic Church perceived or interpreted to be religious heterodoxy. Charles V did not wish to see Spain or the rest of Habsburg Europe divided, and in light of continual threat from the Ottomans, preferred to see the Roman Catholic Church reform itself from within. This led to a Counter-Reformation in Spain in the 1530s. During the 1520s, the Spanish Inquisition had created an atmosphere of suspicion and sought to root out any religious thought seen as suspicious. As early as 1521, the Pope had written a letter to the Spanish monarchy warning against allowing the unrest in Northern Europe to be replicated in Spain. Between 1520 and 1550, printing presses in Spain were tightly controlled and any books of Protestant teaching were prohibited. Between 1530 and 1540, Protestantism in Spain was still able to gain followers clandestinely, and in cities such as Seville and Valladolid adherents would secretly meet at private houses to pray and study the Bible. Protestants in Spain were estimated at between 1000 and 3000, mainly among intellectuals who had seen writings such as those of Erasmus. Notable reformers included Dr. Juan Gil and Juan Pérez de Pineda who subsequently fled and worked alongside others such as Francisco de Enzinas to translate the Greek New Testament into the Spanish language, a task completed by 1556. Protestant teachings were smuggled into Spain by Spaniards such as Julián Hernández, who in 1557 was condemned by the Inquisition and burnt at the stake. Under Philip II, conservatives in the Spanish church tightened their grip, and those who refused to recant such as Rodrigo de Valer were condemned to life imprisonment. In May 1559, sixteen Spanish Lutherans were burnt at the stake: fourteen were strangled before being burnt, while two were burnt alive. In October another thirty were executed. Spanish Protestants who were able to flee the country were to be found in at least a dozen cities in Europe, such as Geneva, where some of them embraced Calvinist