With just over a month left before Prince Harry and Meghan Markle's royal wedding, which is to be held on May 19 in St George's Chapel in Windsor Castle, rumors about the future bride's dress are everywhere. The latest rumors suggest fashion labels Erdem or Ralph & Russo may have been tasked to design and produce the gown, which will be the focus of much attention during the ceremony six weeks from now. In the meantime, here's a look back at some of the most beautiful dresses at royal and princely weddings, including the those worn by Elizabeth II, Grace Kelly, Lady Diana, and more recently Kate Middleton.