Europe Divided: Protestant Reformation & the Council of Trent
As you amble around this lovely town, you'll quickly learn that much of what is notable about it is in some way connected with the historic 16th-century Council of Trent, in which the Catholic church closed ranks against the waves of Protestant reform coming from the north.
In late medieval Europe, power was carefully balanced between the pope and the various kings and emperors. Power was consolidated through an intricate network wherein the secular alliances and post-feudal loyalties of princes, answerable to the Holy Roman Emperor, intersected with an overlying ecclesiastical structure of churches and monasteries, run by powerful bishoprics and answerable to the pope.
In short, by the 16th century, the system had developed to the point where not only the Vatican's strength, but also that of the emperor and other kings, relied heavily on the power structure of the Catholic Church. Therefore, the Protestant revolutions being fired in the north by Martin Luther and other reformers -- who were distressed by the corruption on the part of the official church and its pope in regard to worldly interests -- were seen as much more than a mere argument over style of worship: They threatened Europe's entire power base.
Germanic Holy Roman Emperor Charles V -- who had brought that office to the heights of its power, ruling or controlling much of Europe -- recognized this threat, both to Catholicism and to his domain. But he spent so much of his time and effort fighting wars with France and others that, despite holding his own diets to stamp out Luther's ideas, Protestantism kept growing in Germany. Charles eventually pressured the pope into instituting a great council to refute the reformers, and the Vatican called the council in 1536. But it took another 9 years to settle on Trent as the ideal compromise location in which to hold it, during which time Swiss reformer John Calvin introduced and perfected his own version of Protestantism. On and off for 18 years, from 1545 to 1563, the council held its debates and meetings, to which the Protestants were not really welcome and from which, probably wisely, they stayed away. The Great Council outlasted five popes, Martin Luther (who died in its second year), and Charles V himself (he died in 1556). Calvin passed on in 1564.
Far from taking Protestant complaints to heart, the council took a hard line, becoming more of a defensive strategy session. The Vatican dug in its heels and its doctrine, reorganizing church structure and policies to tighten control rather than loosen it. This became the Counter-Reformation, which, while not quite reaching the terrifying extremes of the Spanish Inquisition, brought the yardstick of conservatism down hard on the knuckles of Catholic Europe.
Still, it was all too late to stem the tide of Protestantism -- and a general progressive slide away from the remnants of feudal power structures. The Germanic countries, soon to be followed by England, increasingly turned their backs on the Vatican. Charles V was the last German emperor to be crowned by the pope. The Papal States and the continent's secular kingdoms drifted apart, and the old power system gradually unraveled as Europe groped its way toward the system of nation-states we know today.