Since the 1930s, when it first emerged as a distinctive field of research, intellectual history has always been fascinated with the Renaissance. Intellectual historians are concerned with unearthing the deep, often half-conscious patterns of thought that govern the way individuals understand and act within nature and society. They examine how traditions of thought situate themselves within changing linguistic and cultural settings. Lately they have begun to focus on the history of learned disciplines, intellectual routines, and practices. Above all they are concerned with the question of why large groups of human beings change their beliefs over time. This being the case, it is easy to see why the Renaissance attracts the intellectual historian. It was a period when fundamental changes occurred in Western societies across a wide range of beliefs, religious, scientific, political, historical, and anthropological. Christendom disintegrated and sovereign states emerged. The Catholic Church lost much of its authority and new Protestant churches and sects appeared. Religious divisions and wars led to the first tentative expressions of the need for tolerance and freedom of expression. Educational ideals and practice were transformed. Humanists arose to challenge the hegemony of scholastic culture. Christian culture underwent a major reorientation in its attitude to the pagan culture of Graeco-Roman antiquity. Republicanism and absolutism crystallized into distinct traditions of political thought. Major changes occurred in how Europeans saw and analyzed human nature, the cosmos, and natural processes. The sciences grew less interested in contemplating nature and more interested in controlling it. A New World was discovered full of societies, flora, and fauna utterly unknown to Western learned traditions.