Harry and Meghan pledged to "honor and protect" each other

Harry kept the beard and yes, wore his uniform! 

Markle becomes a princess automatically by marrying Harry. As she was not born a royal, her title as princess becomes her husband's name so she'll formally be known as Her Royal Highness Princess Harry of Wales.

NBC News WINDSOR, England — America has a new princess.
Los Angeles native Meghan Markle joined hands with Britain’s Prince Harry Saturday as they pledged to “honor and protect” each other in marriage after a 15-month romance. They later kissed on the steps outside the chapel.