The wedding garter tradition originated in the Dark Ages. In "Wedding Customs Then and Now", published in 1919, Carl Holliday paints the following picture of medieval England: “The bridesmaids start with the weary bride to the wedding chamber when suddenly the cry arises, ‘Get her garter’... If the woman has been thoughtful, she has fastened it loosely to the bottom of her dress so that it drags in plain view of the scrambling ruffians; if she has not been a wise virgin, she may find her clothes in rags after the struggle.”
For a guest, having a tatter of the bride’s dress was considered good luck. Crowds of guests became so bawdy that they’d often follow the couple to their marital bed, ripping at their clothes as a form of “encouragement.” And so, the bride and groom started tossing the bouquet and the garters that held up the bride’s stockings as a way to appease the crowd.