Abstract: This publication aims to analyze the economic, social, and cultural phenomena that first appeared in the "era of revolutions" that occurred in the nineteenth to early twentieth centuries. The modern European trend toward tolerance, which is the basis of current social and cultural changes, including in our country, has specific intellectual grounds. The subject of the study was the ideosphere of the nineteenth and early twentieth centuries, including philosophical, economic, and psychological concepts that gave rise to modern trends in these areas. The result of this study was the determination of the reasons that caused the change of the ideological paradigm in Europe. The novelty of the research lies in the fact that, for the first time, the intellectual foundations of the formation of tolerance as an actual socio-cultural phenomenon are analyzed. This article consistently proves that among the first such grounds, it is possible to determine the emergence of machine production and, as a result, the appearance of a mass person with a culture corresponding to them, performing a compensatory and entertaining function. The most important cultural foundation is mainly the intellectual "background" created by the teachings of Friedrich Nietzsche, Karl Marx, and Sigmund Freud. The ideas of Anglo-American pragmatism played a significant role in forming a new morality, which included the denial of religion and its values, giving it a utilitarian character. During the subsequent historical period and at present, these views have become the basis for the creation of the so-called "individual faith," in which religion ceases to be the guide of human life but only serves the needs of the individual. The desacralization of religion leads to the study of different aspects of sexuality, which opens up the possibility for modern thinking about gender. The concept of "natural law" should also be attributed to the intellectual factors of the formation of modern European tolerance.