How did Darwin believe the world began?

Answer 1

It is unclear to me to what degree Charles Darwin might have been a theist, or rather, a deist. He might have allowed for creationism in some form, where through some intelligent agency the first single celled lifeforms were put on Earth, in the expectation that they would multiply, evolve and produce complexity. But more likely he believed that the first life was the result of natural processes. There's a link below analyzing Darwin's beliefs on the subject.

What sources available to me don't tell me is what Darwin believed about the origin of the planet and the universe. He lived in a time where the age of the Earth and the cosmos were still very much in dispute, and no single preferred hypothesis existed to explain their origin. He might have subscribed to something like the Kant Nebular Hypothesis, or he might have speculated along very different lines - if at all.