No-one knows for certain where olive cultivation originated. There are two theories about this; one suggests that it started in Syria, Lebanon and Israel, and the other that cultivation began in Asia Minor.
One thing that definitely seems to have been proven is that it was brought to Europe in around 1050 BC by the Phoenicians. Olives were first introduced to Cyprus, Crete and the Aegean islands, and later spread to Greece and Italy. The first signs of olive trees on the Spanish Mediterranean coast came during Roman rule, but it was the Arabs who later really boosted its cultivation in Andalusia.
Despite the fact that nowadays olive trees have been planted all over the world, the Mediterranean is still the place where most of production takes place, and Spain is currently the country with the most olive trees and the highest olive oil production in the world.