To this day, Portuguese historiography has not produced a synthesis work on such a curious fact of our history: the expulsion of the members of the Society of Jesus by the republican regime. It was the only time that in the twentieth century there was a mass expulsion among us of individuals who had only the fact that they belonged to the same religious congregation. unified by “classes” or “categories”, regardless of any acts they had performed. Much less did they encompass people whose only common denominator was belonging to a religious order or sharing a belief. But, strictly speaking, this "class" was an abstraction. What was expelled in 1910 were concrete, determined people, some of whom would not return to their country. The expulsion of the Jesuits was decidedly a singularity of the First Republic. Understanding this fact is the purpose of this paper.