Origins of Religion and Moral is part of a series of articles published by the French anarchist-geographer Jacques Élisée Reclus between the end of the 19th century and the beginning of the 20th in which the thinker presents his reflections on various subjects in evidence in the social thought of this period. Several of these texts, related to themes such as religion, education, progress, family, food and marriage, served as the basis for the final writing of some chapters of his great literary work The Man and the Earth. In the text now presented, the author dedicates his considerations to the understanding of the genesis and of the relations between moral and religion, showing, through the analysis of social practices created and reproduced by different peoples throughout the history of humanity, that fear, attempts to explain the unknown phenomena that occurred in nature and the action of priests are fundamental elements to understand specific religions and morals existing in different parts of the world. Besides that, emphasizes that the reproduction of irrationalities such as those that promoted the emergence of rituals of sacrifice of people and animals are important elements for understanding the development and consolidation of different religions and these irrationalities were aligned with the interests related to the maintenance of power