When and Where did the Atomic Theory Come From?

[Rhondazvous]

Also, Islamic scientists like Al-Ghazali and Averroes had some atomist theories, but, surprisingly, it went over fairly well.

Back in the west, a transitional theory called Corpuscularianism (like atomism, only it's still potentially divisible, allowing for alchemy) became popular starting in the 17th Century (notably starting with a treatise by Galileo called Discourse on Floating Bodies, which presumably got overshadowed by his defense of Copernicus), with luminaries like Descartes, Newton, Boyle, and Hobbes (who actually used it to justify some of his arguments on politics in Leviathan).

Of course, that changed, and I'm inclined to think Seele, Priestley, and Lavoisier's independent and nigh-on-simultaneous discovery of Oxygen may have been the initial tipping point, especially after Lavoisier published an Elementary Treatise of Chemistry, listing 33 elements. My guess is, after that, it was only a matter of time before atomism truly went back into vogue.

"Corpuscularianism"
One moment, please, while I untangle my tongue. This could be a very delicate operation, and I may need a local anesthesia.

It seems that what we call the age of discovery was actually the age of rediscovery, or rather using modern technology to build upon what was already known to a rudimentary extent by the ancients.