Aren’t they only allowed to marry nobles? Or was this a case of true love? 😀
While many British Royals have contracted dynastic marriages with other royals, there is no reason why a commoner may not marry into the British Royal Family. Technically, Prince William’s mother, the former Lady Diana Spencer, was herself a commoner.
She was born The Honourable Diana Spencer, daughter of John Spencer, who, as the heir to the Earl Spencer, was permitted to style himself as Viscount Althorp. When John Spencer became Earl Spencer, his children were permitted to style themselves as Viscount Althorp (his son James) and ‘Lady’ (Diana and her sisters, Sarah and Jane). These titles (Honourable, Viscount (as heir), Lady) are a courtesy extended by the monarch (although permission is rarely denied), not a right or entitlement.
Prior to this, James II, Henry VIII, and Edward IV all married commoners.