On November 24th, 1859 Charles Darwin published "On the Origin of Species." This book explored the ideas of natural selection and hinting at the evolution of humans, going completely against the Christian idea of Creation and where man came from in the beginning. Darwin himself used to be Christian but lost his faith as he grew older and suffered the loss of his daughter. Rising scientists during this time agreed with Darwin's ideas, although there were some that did not. His associate Thomas Huxley became known as "Darwin's Bulldog" because of his vehement defense of Darwin's work, as is seen in the "Huxley vs Wilberforce event on this timeline. The ideas in Darwin's novel changed the way humanity looked at the world, and gave way to an increase in the belief in science over religion.

Sources:

https://www.britannica.com/biography/Charles-Darwin/On-the-Origin-of-Spe...