I'm naming my daughter after the Dutchess Anastasia. Since I work for Disney, we wanted to name her after a princess; and my husband is half Russian, so we wanted to represent his heritage.
the name Rhiannon means great queen
Diana
George
William
Charles
Harry
Sara/Sarah means princess
Augustus, Maximilian, Regina, Regus, Rex
All of the ones listed above are old European names that have been used in royal families. If you want to find more you can look into the history of other countries too.
Mary, Henry, Edward, Francis, Isabella, Marie, Ann
Elizabeth, Victoria, Charlotte I can't thick of others . I'm not sure If the are royalty but I know there are associated with royalty.