The couple tied the knot in the groom's 18th century family estate - the Liria Palace in Madrid - before a long lunch on the lawn where guests were served wine and beer from the family's own brewery located nearby.
A 750-strong guestlist included Queen Sofia of Spain as well as a host of society figures from royalty to fashion designers.
The bride beamed in an elegant short sleeved gown designed by her aunt Teresa Palazuelo, which featured a dramatic detachable train. Her brother did the honours of walking her up the aisle.
The bride, who has worked in PR for couture heavy hitters Oscar de la Renta and Carolina Herrera in New York, finished her look with a traditional lace veil, which she wore over her shoulders throughout the service. She carried a rustic green bouquet which included Astilbe, Scabiosa milki scoop, Veronica smart Luna monocaule, Diosma and simple white roses tied with a thin ribbon.
Groom Don Fernando Juan Fitz-James-Stuart y Solís-Beaumont, 28, wore full military regalia representing the Royal Cavalry Armory of Seville.
The couple's first dance was to a waltz, which took place before guests QUICKLY took to the dancefloor where they spent the remainder of the festivities - which reportedly went on long after a midnight curfew.