Why did ancient roman war engagement ring on the third finger of the left hand?

Ancient Romans believed that the third finger of the left hand, known as the "ring finger," contained the "vena amoris," or the vein of love, which was thought to connect directly to the heart. This romantic notion made it a popular choice for engagement rings, symbolizing love and commitment. The tradition carried on through the ages, leading to the modern custom of wearing wedding and engagement rings on that finger.