This gem has a provenance similar to another huge Scandinavian diadem: Empress Joséphine's Emerald Tiara, now in the possession of Norway's royal family. The sapphires are thought to have been a wedding gift from Napoléon to Princess Augusta of Bavaria, Duchess of Leuchtenberg, when she married Eugène de Beauharnais (Empress Joséphine's son).
Left to Right: Queen Victoria, Queen Louise, Princess Sibylla, Princess Birgitta
It makes the journey to Sweden with Augusta's daughter, Josephine, who was the Queen consort of Oscar I of Sweden and Norway. The parure is now in the family foundation in Sweden, and has been worn mostly by queens and those acting as first ladies of the country, though there are exceptions to that rule: one being when King Carl Gustaf's sister, Princess Birgitta, wore it for Carl Gustaf and Silvia's pre-wedding ball in 1976.
Birgitta's outing of the sapphires was the last time they were worn by anyone other than Queen Silvia (to date). She's made this one of her staples, and has explored all sorts of color combinations with the luscious blue sapphires.
It's also flexible in form: the tiara is comprised of 11 separate sections, meaning you can adjust the circumference to suit your needs (it even stores flat in its case, which is quite interesting). This tiara is large and surely has a significant weight to it - but it is still a favorite, and I wonder if the flexibility factors into that. Surely the ability to form it to suit your head shape makes for a more comfortable tiara-wearing experience.
The tiara is the headliner in a full parure of jewellery. Today, that parure is composed of the tiara, earrings, a necklace, a brooch, and two hairpins. The earrings are relatively new to the set: Queen Victoria didn't wear earrings, so she either gave the originals away or had them remade into something else. Queen Louise (as Crown Princess) converted two of the four original hairpins into a set of earrings to complete the parure once again.