In the evening, the great and gilded descended upon the Palace for the state dinner, which saw Queen Mathilde wear a glittering golden gown as she and her husband were celebrated as guests of honour. The Belgian royal family possesses a somewhat narrow collection of heirloom jewels, and Queen Mathilde opted for what is surely the most historic tiara in the vaults – the Nine Provinces tiara, a piece with a troubling and tragic past that has become the trademark jewels for the Queens of Belgium.

Queen Mathilde of Belgium wore the Nine Provinces tiara at the state banquet
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The tiara dates back to 1926, when it was gifted to the new Crown Princess Astrid on the occasion of her wedding to Crown Prince Leopold (the future King Leopold III) by the Belgian government. An Art Deco piece, the meander base is topped with eleven diamonds, which at the time represented the nine provinces of Belgium, Congo (then a Belgian colony) and the royal family. Van Bever created the tiara using diamonds from Congo – where King Leopold II’s Colonial rule, described in 1999 as a ‘hidden holocaust’, was so brutal that it was condemned by other European colonialists in 1908.
Nevertheless, the tiara became a staple for the Queens of the Belgians. Crown Prince Astrid made her debut in the Nine Provinces tiara at the Bal de la Grande Harmonie in 1927 and notably wore it at the wedding of her sister-in-law, Princess Marie Jose of Belgium, to Crown Prince Umberto of Italy in 1930. As Queen, Astrid wore the tiara for a number of official portraits as well as for the wedding gala in honour of Crown Prince Frederik of Denmark and Princess Ingrid of Sweden. Tragically, that occasion came just months before she died in a car accident.
King Leopold III remarried following Astrid’s death, through his new bride, the Princess de Réthy, never wore the tiara in its full version, preferring to adapt it into bracelet or choker forms.