Olives have been cultivated for nearly as long as Western civilization has been recording its history. Probably six or seven thousand years ago; beginning in Crete and Syria. Three thousand-year-old mummies have been found preserved in olive oil, and cured olives were often left in the tombs of the Pharaohs to tide them over in the afterlife.
The olive eventually spread around the entire Mediterranean, and wherever it was cultivated the olive tree, its fruit (the olive is technically a fruit) and the precious oil extracted from the olive entered into the culture and mythology of the region, becoming objects of reverence with religious significance. The Old and New Testament, the Koran and the Mythologies of other ancient Mediterranean peoples are full of references to the holy and healing powers of the olive.
In Judeo-Christian tradition, the dove brought Noah an olive branch as a sign that the world was again at peace after the flood and that it was once again safe to come out. Olive oil was used as the holy anointment; Jerusalem was found at the foot of the Mount of Olives.
The ancient Greeks believed that the olive tree was a gift of the gods. It was said that Zeus, the king of the gods, decided that he would give the patronage of Athens (the jewel of the ancient Greek world) to whomever among the gods would make the most useful invention. Poseidon (god of the seas) created the horse - the ultimate (at that time) weapon in war - and Athena (the goddess of wisdom) produced the olive tree - the fuel of lamps, salve of wounds and provider of nourishment. Zeus chose the more peaceful gift, and Athena became the patron of Athens. The olive tree was so revered among the Greeks that in the time of Solon, "the Lawgiver", it became a capital offence to kill one or to cut it down.
The Greeks brought the olive tree to Italy (probably first to Sicily) and the Romans brought it to the rest of the world. In fact some have postulated that it was Rome's ever-increasing need for more and more olive oil -for food, fuel, medicine, axle grease - that drove her to expand her empire. When the Romans expanded into Spain, North Africa and Southern France, they found olive tress already growing. The Romans taxed the province of Tunisia three hundred thousand gallons of olive oil yearly. They raised the art of olive cultivation and curing to its highest level and were the inventors of the screw press for extracting olive oil; technology that remains essentially unchanged to this day. Ancient Roman recipes (De re coquinara of Apicius) abound for all kinds of pickled and cured olives, cakes and breads made with olives and other dishes cooked with olives. Olives has been found still preserved in the ruins of Pompeii.
In the early fifteen century the olive came to the Americas with the Spanish, first to South and Central America and then eventually California. Today olive cultivation has spread throughout the world to Australia, South Africa and even China. It is estimated that there are about 800 million live tress planted worldwide. The trees take five to ten years to reach fruit bearing age and some live for as long as six hundred years. Ninety percent of the world's olive production remains in the Mediterranean, and eighty percent of the olives produced worldwide are consumed in the country in which they are grown. Olives earmarked for the table are picked by hand to preserve their texture.
There are about seventy-five different varieties of olives cultivated seriously today - many more ancient varieties have been lost over the years. Olives are inedible right off the tree. Just picked they contain an acrid tasting, bitter compound called oleuropein which is found only in olives. Olives used to make oil are not affected by this, but olives destined for eating must be cured in order to separate and remove the oleuropein. They are either soaked in oil for several months ("oil cured"), soaked, rinsed and resoaked in water for many months ("water cured"), soaked in brine for one to six months ("brine cured"), packed in salt ("dry cured") or soaked in an alkaline solution ("lye cured").