a valid sacrament, but confined this to cases where it was literally administered by physical force: a person who had consented to baptism under threat of death or serious injury was still regarded as a voluntary convert, and accordingly forbidden to revert to Judaism. After the public violence, many of the converted "felt it safer to remain in their new religion." Thus, after 1391, a new social group appeared and were referred to as conversos or New Christians. Many conversos, now freed from the anti-Semitic restrictions imposed on Jewish employment, attained important positions in fifteenth-century Spain, including positions in the government and in the Church. Among many others, physicians Andrés Laguna and Francisco López de Villalobos (Ferdinand's court physician), writers Juan del Enzina, Juan de Mena, Diego de Valera and Alonso de Palencia, and bankers Luis de Santángel and Gabriel Sánchez (who financed the voyage of Christopher Columbus) were all conversos. Conversos—not without opposition—managed to attain high positions in the ecclesiastical hierarchy, at times becoming severe detractors of Judaism. Some even received titles of nobility and, as a result, during the following century some works attempted to demonstrate many nobles of Spain were descended from Israelites. The "Enforcement Across Borders" hypothesis According to this hypothesis, the Inquisition was created to standardize the variety of laws and many jurisdictions Spain was divided into. It would be an administrative program analogous to the Santa Hermandad (the "Holy Brotherhood", a law enforcement body, answering to the crown, that prosecuted thieves and criminals across counties in a way local county authorities could not, ancestor to the Guardia Civil), an institution that would guarantee uniform prosecution of crimes against royal laws across all local jurisdictions. The Kingdom of Castile had been prosperous and successful in Europe thanks in part to the unusual authority and control the king exerted over the nobility, which ensured political stability and kept the kingdom from being weakened by in-fighting (as was the case in England, for example). Under the Trastámara dynasty, both kings of Castile and Aragon had lost power to the great nobles, who now formed dissenting and conspiratorial factions. Taxation and varying privileges differed from county to county, and powerful noble families constantly extorted the kings to attain further concessions, particularly in Aragon. The main goals of the reign of the Catholic Monarchs were to unite their two kingdoms and strengthen royal influence to guarantee stability. In pursuit