Look how my ring encompasseth thy finger,
Even so thy breast encloseth my poor heart;
Wear both of them, for both of them are thine.
Richard the Second: William Shakespeare, 1593
The ancients believed that the third finger, left hand, had a special vein, vena amoris, the vein of "love" running from this finger directly to the heart. While having no basis in scientific anatomy, the romantic custom still stands. King Edward VI of England designated the third finger, left hand, as the ring finger and in 1549 the Book of Common Prayer designated the left hand as the marriage hand.
In all ancient cultures the circle was considered to be the symbol of perfection; it is perfect unity, without beginning or end. It is the symbol of the sun, earth and universe, and represents holiness, perfection and peace. The caveman bound himself to his mate with a cord of woven rushes to symbolize their spirits as one. The ancient Northerns believed that a lovers knot symbolized love, faith, and friendship. The hair of the beloved was woven into such a knot, and was worn as a ring. Among the Anglo-Saxons a part of the "wed" was a ring worn on her right hand.
The word "betrothed" derives from the Anglo-Saxon "troweth", meaning truth. Thus betrothed means giving a truth or pledge. The engagement ring indicates to all that she has pledged her love to one man. The Greek "adamant" means steadfast or invincible, and it is from this word that the diamond gets its name. Diamonds were believed to be invincible, chosen to symbolize purity and light, and as protection against the dark forces of evil. It was believed that its sparkle arose from the lovers' fires, and that it possessed great harmonizing powers. The icy fire of the true white diamond is still the symbol of love.
Maximillian of Austria really wanted to marry Mary of Burgundy, but was afraid she would not accept his proposal. He was advised to buy her a diamond. He did, she accepted, and they were married on August 17, 1477. This is the first reported diamond engagement ring.
The wedding ring is the concrete sealing of the marriage pact. In every ancient culture can be found rings with inscriptions and designs denoting them as marriage rings. In the 12th century Pope Innocent the Third ordained that marriages must be celebrated in the church, and that the ceremony must include a marriage ring. Consequently, the wedding ring has a religious significance that is lacking in the engagement ring. The wedding ring is placed on the ring finger first to be closest to the heart.