Ancient Egyptian leaders took an oath of office with their right hand on an onion. The onion symbolized eternity because of its circle-within-a-circle structure.
Paintings of onions appear on the inner walls of the pyramids and in the tombs of both the Old Kingdom and the New Kingdom.
As early as the building of the Pyramids, the onion was a part of the basic rations for sailors because it helped to prevent scurvy during long voyages without fresh foods. Army quartermasters valued it for the same reasons.
The onion is mentioned as an Egyptian funeral offering and is depicted on the banquet tables of the great feasts. Frequently, a priest is pictured holding onions in his hand or covering an altar with a bundle of their leaves or roots.
Frugal Egyptian peasants adopted the onion to relieve the monotony of their diet, often eating them raw. Egyptian onions were said to be large, white and mild.
Know more trivia about onions at SweetOnionSource.com.