Proxy marriage

A proxy marriage is when two people are getting married separately, but are getting married to one another. It was common for European kings and nobles to be wed by proxy marriage. Napoleon I of France was wed by proxy marriage to Marie Louise, Duchess of Parma. Catherine of Aragon wed Prince Arthur by proxy. A famous 17th-century painting by Peter Paul Rubens shows the proxy marriage of Marie de Medici. 
Today, this form of marriage is illegal in most countries, or it requires a special permit. It is still legal in some US states, and in a few Islamic countries