The modern conception of the "Promise Ring" is an innovation from the 1990s that essentially symbolizes commitment to a specific individual, usually a girlfriend or boyfriend.  However, the idea behind the ring – commitment to a specific individual - dates back to Ancient Greece and quite possibly as far back to biblical times.

In biblical times, upon a formal betrothal, which in essence was a marriage contract, a man would give his future bride a ring to basically promise that a marriage was forthcoming.  This was the earliest form of the promise ring, although it actually was in effect the earliest type of engagement ring known to mankind.

The next group of people to use promise rings were the Greeks; however, their purpose of using a promise ring was not related to marriage or relationships.  Instead, the Greeks viewed a ring on a finger as essentially serving the same purpose as a red thread around the finger – as a constant reminder or a pledge so as not to forget something.  Obviously, a ring represented a pledge or reminder of great importance, such as the iron promise ring worn by Prometheus to remind himself not to raise the ire of Zeus.

Following the fall of the Greek Empire, the Romans had a practice of using promise rings.  However, these rings were along the lines of the betrothal rings from biblical times and thus may not necessarily qualify, even though they did symbolize a commitment.  The most common promise rings was called anAnulus pronubusand it consisted of two iron rings with oval plating that had the names of the betrothed couple engraved on it.  It can be assumed that the ring the groom and bride wore the rings with other's name engraved on it.  Later, once it became legal for all Romans to wear gold, iron was replaced by gold and became the first gold promise rings.

During the middle Ages, there was no recording of the use of the promise ring.  This is most likely because of the influence of the Catholic Church, who required adherence to traditional Christian marriage rules, which did not involve promise rings and instead used an engagement ring.  In addition, during this period of time, the masses could not afford a ring of this nature, due to the feudalist government in place.  However, the only appearance of promise rings, ironically enough, was in the Church, where Bishops wore rings to pledge their spiritual union with the church.

During the 16th and 17th centuries, promise rings reappeared and took a few different forms.  The most common type of promise ring was the "friendship ring" that represented a promise to wed in the future, once the man was financially secure enough to support a wife.  A second type of promise ring was the "poesy ring."  This ring was engraved with poetry that basically promised fidelity to a lover or friend and might have a French saying such as "Vous et nul autre" -- "You and no other."  A third variation was the "scribbling ring," which was set with uncut diamond crystals.  Lovers used the exposed points of the diamond to etch romantic vows into windowpanes.

During the 20th century, the promise ring could be given by a man or woman.  It was usually surprise gift and was something either part could accept or deny.  The most common practice, however, was for women to give a promise ring to their man.  In the present day in the year 2010, the promise ring takes several different formats:

The first type of promise ring is the Pre-Engagement ring.  This ring is basically a form of committing to a long-term relationship while not actually proposing marriage.  The second type is called a Purity Ring and it essentially represents the wearer's refusal to engage in any sexual activity until after marriage.  A third type is a friendship ring that basically shows the two friends are basically best friends forever.  The next type is the promise ring that has the purpose of serving as a reminder to do a certain action or an attachment to a specific cause.  The final type of promise ring is the ring that teenagers give each other.