LastNovember , Prince Harry shared his plans to marry American actress Meghan Markle with the world , but it was n’t until March 15 , 2018 that their engagement became " prescribed . " That ’s when Queen Elizabeth II releaseda statementgiving her formal consent for the couple to we d. Without it , their marriage would have been considered invalid under a British jurisprudence that dates back to the 18th century .

According toTown & Country , the 1772 Royal Marriages Act stated that all marriages to a extremity of the British royal kinfolk were subject to the approval of the prevail monarch . The legislative act [ PDF ] show : " … every marriage , or marital contract , of any such descendent , without such consent first had and hold , shall be void and null to all intention and purposes whatsoever . "

This rule received an update in 2013 with the release of the Succession to the Crown Act . Today , only the first six royal stag inline to the thronerequire the monarch butterfly ’s permission to formalise their marriages . That means that for Prince Harry — who was 5th in stemma when he announced his engagement , but strike hard into sixth situation in April with the birth of His Royal Highness Prince Louis of Cambridge — getting Granny ’s approving was vital . Meanwhile , Harry ’s cousin Princess Eugenie ( who ’s ninth in line ) will be gratuitous to get married this fall with or without a thumbs - up from the Queen .

Chris Jackson, Getty Images

The Succession to the Crown Act became relevant late last calendar month when Prince William and Kate Middleton welcomed child Prince Louis into their family . Under theold laws , the birth of a boy would have bumped Princess Charlotte down a pin in the line of succession , but thanks to the new number she ’s the first distaff royal to maintain her spot over a younger male sibling .

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