This article contains my original, un-edited contributions to Wikipedia’s “History of Chemistry” article from a few years back.
It can be said that chemistry would have “started” when it was possible to distinguish it from alchemy. This would not have happened until Sir Francis Bacon built on the work of Descartes and suggested a scientific method of inquiry. That would not have been at least until the 1600’s. Its application to chemistry still took longer, as many “chemists” of the day still had a poor understanding of the chemicals they were working with.
But what about the idea of atoms (atomism)? How far back can we go?
Atomism can be traced back to 440 BCE in ancient Greece, as what might be indicated by the book De Rerum Natura (The Nature of Things) written by the Roman Lucretius in 50 BCE. In the book was found ideas traced back to Democritus and Leucippus, who declared that atoms were the most indivisible part of matter. This coincided with a similar declaration by Indian philosopher Kashyapa Kanada in his Vaishe Shika sutras around the same time period. Kashyapa arrived at his sutras by meditation. By similar means, he coined a form of Newton’s Third Law, and discussed the existence of gases, a substance not mentioned in Europe until Robert Boyle proved its existence over 1000 years later. What Kanada declared by sutra, Democritus declared by philosophical musing. Both suffered from a lack of empirical data. Without scientific proof, the existence of atoms was easy to deny. Aristotle opposed the existence of atoms in 330 BC; while on the Indian sub-continent, the study of the Vaishe Shika was suppressed almost until the 20th century.
Aristotle was rediscovered by St. Thomas Aquinas and alchemist Roger Bacon in the 1200s. In Europe, the Church raised Aristotle’s writings almost to the level of scripture, associating atomism as some form of heresy.
The rise of metallurgy
It was fire that led to the discovery of glass and the purification of metals which in turn gave way to the rise of metallurgy. During the early stages of metallurgy methods of purification of metals were sought, and gold, known in ancient Egypt as early as 2600 BCE, became a precious metal. The discovery of alloys heralded the Bronze Age. After the Bronze Age, the history of metallurgy in Europe (and indeed the world) was marked by which army had better weaponry. Countries in Europe and Asia had their heydays when they made the superior alloys, which, in turn, made better armour and better weapons. This often determined the outcomes of battles.