Feudal Europe, this historic period that allowed the extreme taxation of the Catholic Church and its logic restrictive, intolerant and even fanatical, delayed by centuries of human advancement. Faith, governed under almost unbearable burden of sacraments, determined in the end, the emergence of several critical thinkers, religious and political, who tried to revive primitive Christianity. The lofty and artistic power of the Renaissance, the advance of science and the humanities, the era of the conquest of new and unimagined territories and the decline of Scholasticism, generated in man a new sense, courage and character who bowed to the knowledge and the embrace of the books. From this accumulation of facts, was born the so-called Protestant Reformation and later, by an effect infinite chain of causes and effects, the outbreak of the War 30. Tackle this complex issue. The Protestant Reformation is certainly the perfect prelude to this long series of wars (not necessarily religious) that between 1618 and 1648 drew to its center of gravity almost all of Europe. The Protestant Reformation, driven primarily by Martin Luther and John Calvin, leaders of Lutheranism and Calvinism later respectively, were with their pros and cons a genuine renewal of faith in Christ and a hard blow to the Church, which was late responding and rushed to The Counter, that new set of measures dogmatic, administrative, authoritarian and repressive, which further divided the Christian world. Soon Lutheranism and Calvinism lesser extent, gain followers. However, it is important to say that the spread of these doctrines was due more to political and vindictive intentions territorial than faith itself.