Legend has it that a French pastry chef visiting England in Anglo-Saxon times noticed the English tradition of piling small cakes and sweet rolls on top of each other the bride the bride and groom would attempt to kiss over the stack cakes without knocking them down. The chef returned to France, piled the cakes and rolls into a tower, perhaps covering them with frosting and creating what would become the forerunner of our modern wedding cake.
In Bermuda, where I lived as a child, the traditional wedding cake is three-tiered with one layer for the bride, one for the groom and one saved for the guests.