Posted by Henri M on October 25, 2012, 11:09 am, in reply to "OT: title for groom"
I am not sure if Mr Westling did receive the ducal title ad personam. I thought his ducal style is, like in Spain, a titulus iure uxoris (a title used in the name of the spouse). When Don Jaime divorced the Infanta Elena, Duchess of Lugo, he automatically lost the ducal style.
When Mr O'Neill will be treated the same, then he will become Duke of Hälsingland and Gästrikland by virtue of marriage and not by his own right.