For those wondering whether Meghan Markle will now be known as a princess, the answer is an emphatic 'no'. In order to be called a 'princess', you have to be born into royalty. Markle's new official title will be Her Royal Highness Princess Henry of Wales. Diana was made a princess by the media, not by the royal family.
It is, however, possible that the Queen will confer upon the young couple, the titles of Duke and Duchess of Sussex respectively on their wedding day. Such a decree will elevate Markle to the same level as her husband.
Children born to the couple, while Queen Elizabeth II is still alive will be Lords and Ladies, as opposed to Princes and Princesses. Their full title will be Lord or Lady Mountbatten-Windsor.
Markle is one of a long line of Americans marrying into European royalty. Some of her illustrious predecessors include Grace Kelly, who married Prince Rainier III of Monaco, and Wallis Simpson, who married King Edward VIII of the United Kingdom. In the case of the latter, the king had to abdicate the throne.
Co-incidentally, Edward VIII was sympathetic to the Nazis, while Prince Harry once got into trouble for wearing a Nazi uniform. However, the latter incident was nothing more than a childish mistake.
Co-incidentally also, Wallis Simpson and Meghan Markle are divorcees. The latter, however, is biracial. This is a first for the royal family.
At present, there is a Canadian in the royal family. And she happens to be a Montrealer. Autumn Kelly is married to Peter Phillips, son of Princess Anne, and oldest grandchild of the Queen.