Although we know from written sources that the Greeks painted pictures from the Bronze Age through to the Roman conquest and beyond, most of them have been destroyed and very few of them survive. It may seem strange that more of the older paintings survived than the more recent ones. This is because some of the Bronze Age paintings were buried by volcanoes (as at Pompeii) and others were buried by earthquakes, and so they were not destroyed and archaeologists were able to dig them up. The few later paintings that survive were mostly painted on the walls of tombs, underground, and that is how they survived safely.
The earliest real paintings we have from the Greek world are from the Minoan culture on the island of Crete. They were painted on the walls of palaces where the rulers of Crete lived, around 1700-1400 BC, and when the Myceneans destroyed the palaces around 1400 BC, some of the pictures survived buried under the ruins of the palaces.
Another set of pictures, about the same time, comes from the island of Thera (also called Santorini), in the middle of the Aegean between Crete and Greece. The main city on Thera, Akrotiri, was buried by a volcanic eruption around 1600 BC