Some time around 100, 000 BC, we were already making paints. Red and yellow pigments were found on-site, along with tools that may have been used to make a paste. The fact that paints were available at this time may mean that it’s creators were capable of complex though. A couple of signs point to sophisticated cognition; to make paint, you need to be able to plan and experiment, and the use of paint seems to imply symbolic thought, meaning it’s creators must have been imaginative.
The year is close to 20, 000 BC, and we have cave paintings. Paints before this time may have been used on the body, but at this point we have complex representation of animals in our cave paintings. There were paintings of the outline of hands up to 40000 years ago, but these paintings are a bit less sophisticated than the depictions we see later, which also use more complex pigments.
By the Classical Era, humans had learned to mix pigments together to make more vivid paint. One particularly dangerous method of making paint was by mixing hot mercury with sulphur; at this time, medical knowledge was limited, and the dangers of mercury were little known. A deep blue was unobtainable by Europeans until the Middle Ages, when they began to use lapis lazuli from trading partners in Afghanistan. The “ultra” in ultramarine doesn’t mean “extreme”, it means “beyond” as in “beyond the sea”, because of its foreign origin.
Prior to the 15th century, eggs were often used as binders for pigment; when oils came in, they were difficult to use. Jack van Eyck, a Flemish painter, did not invent oil paint, but popularized many techniques that allowed oil paints to be used more easily.
The 18th century saw synthetic pigments being created, the first of them being Prussian Blue. The 19th century saw an explosion of variety in the types of colours that could be used, as industrialization boosted the supply, and thus lowered the cost, of paint.
During the 20th century, paints gained a lot of the qualities we see used today. They became less toxic as our understanding of medical science increased, and pigments like arsenic and lead were replaced. Acrylic paint was invented during World War II, and remains the standard for high quality interior painting today.