I know what you mean. I have a fairly good layman's understanding of evolution. Whenever I've been engaged in a discussion on the topic, I'm amazed by the level of ignorance that's often displayed. Especially when people repeat absurd statements like "survival of the fittest" which have no bearing whatsoever on evolution.

were there not atheists long before evolutionary theory?

Few, because they didn't have an answer to the problem of design.

(Plus, back then, science and industry had yet to give a stunning demonstration of the power of human reason over nature.)