The history of anti-Protestantism in France during the Third Republic has been recently revisited by historians such as Jean Baubérot and Valentine Zuber. The latter have shown how “traditional” anti-Protestantism, driven and expressed both by Secularists and Catholics, was truly politicized in the second half of the nineteenth century, in order to serve a nationalist agenda. Expressions of hatred towards a religious minority were to be found in the United Kingdom at the same time period. There, in a Protestant majority setting, the Catholic minority was targeted in ultra-Protestant discourse and actions. The present article studies in a comparative perspective the manifestations of two “anti” movements which were totally at odds in their objects of hatred –Catholics on the one side of the Channel, Protestants on the other– but similar in the methods they employed. In terms of its methodology, this article partly relies on the typology drawn up by the political scientist Anatole Leroy-Beaulieu in his book Doctrines of Hatred, first published in 1902.