Others believe that onions originated in central Asia. The National Onion Association says onions were first grown in Iran and Pakistan. It's difficult to say in which area onions originated as several hundred varieties of onions grow wild in temperate climates all around the world. The Egyptians left onions in their tombs about 3,500 years ago. In fact, the mummy of King Ramses IV, who died in 1160 B.C., had small onions in the eye sockets, probably because they had some spiritual significance and because they replicated a real eyeball.
Many early documents tell of onion cultivation and use.
The great food historian, Waverly Root, cites a Sumerian text dated to about 2400 B.C. that tells of someone plowing of the city governor's onion plot. The Roman writer Pliny the Elder wrote of onions grown in Pompeii. When Pompeii was excavated, archaeologists found cavities in the gardens where the onion bulbs had grown, just as he had written. Texts from India dated to the early 6 th C. write of the onion's use as medicine. They were used as a diuretic, and taken for the heart, the eyes and the joints.