The leaders (Lenin, Marx, Engels, Trotsky, etc.) of the 1917 Russian Revolution were not atheists. They were anti-Catholic, Masonic Jews, bound by their oath to Lucifer.
This is specifically why also in 1917, Our Lady of Fátima ordered the consecration of the world to avoid the spreading of the “errors of Russia.”
Apocalypse 12:1: And a great signe appeared in heaven, a woman clothed with the sunne, and the moone under her feet, & on her head a crowne of twelve starres:
Apocalypse 12:2: and being with child, she cried also traveling, and is in anguish to be delivered.
Apocalypse 12:3: And there was seen another signe in heaven, and behold a great red dragon having seven heads, & ten hornes: and on his heads seven diadems,
Apocalypse 12:4: and his tail drew the third part of the starres of heaven, and cast them to the earth: and the dragon stood before the woman which was ready to be delivered; that when she should be delivered, he might devoure her sonne.
Learn more about Jewish Communism in the Fatima Movement Sections:
Manifesto of the Jewish Communist Party
Protocols of the Learned Elders of Zion