The ring finger is a finger we typically give little thought to, unless it concerns engagement/marriage. Even then, not much thought is given as to why the fourth digit on our hand is called the ring finger. The ring finger has a special significance to it, depending on the culture. It could be magical, medicinal, or victorious. Whatever its significance, there was a common belief (before the human anatomy was modeled) that a vein from the left ring finger ran directly to the heart, the vein of love (Vena amoris). As a part of that, rings too bore a significance depending on the culture. Early rings were made of hemp, leather, bone, or ivory, with metal eventually taking over.
Particularly notable is that rings made of precious materials (gold and silver) signified that a husband trusted his wife (wedding rings in Western culture was traditionally only worn by women. As you may note, both marital partners today wear their wedding ring). Whether or not the wedding ring was worn on the left or right hand also varied by culture; left hand is common because the vena amoris was considered to just be on the left ring finger. However, those that do it on the right (usually done by European countries). applied vena amoris to the right hand instead.
Romans’ decision to wear theirs on the right was because they saw the left hand as wicked, dirty, and impure; at least they have a clear reason for their decision. Because of tradition, if one wanted to signal that they’re engaged (in the US), it’s logical to just wear the ring where it’s been for the past centuries. As to how this all came about, alongside variations in where a wedding ring could be worn it was a mashing of many factors: legend, myth, and even marketing by the jewellery industry.
I thought all this was interesting, more so because of a special something that has happened to me…