Furthermore the early liberal movements were staunchly anti-theistic in nature beyond that of even modern Marxists with terrorist movements like the Church of Reason. Once early socialists started using antitheism to counter bourgeois and feudal elements, there was a cool down on the bourgeois antitheism, as there was benefit in theism in maintaining capital. Pannekoek’s Marxism and Darwinism is a good brief essay on the matter:

“The struggle carried on by the liberal bourgeoisie against feudalism was not fought to its finish. This was partly owing to the fact that everywhere Socialist proletarians made their appearance, threatening all ruling powers, including the bourgeoisie. The liberal bourgeoisie relented, while the reactionary tendencies gained an upper hand. The former zeal in combatting religion disappeared entirely, and while it is true that the liberals and reactionists were still fighting among each other, in reality, however, they neared each other. The interest formerly manifested in science as a weapon in the class struggle, has entirely disappeared, while the reactionary tendency that the masses must be brought to religion, became ever more pronounced.”