Filmed in Hovet, Norway, in 2011, on May 17, also named Syttende Mai, or Constitution Day.
Syttende Mai, Norwegian Constitution Day is the National Day of Norway and is an official national holiday observed on May 17 each year.
The Constitution of Norway was signed at Eidsvoll on May 17 in the year 1814. The constitution declared Norway to be an independent nation. The day focused originally on the Norwegian constitution, but after 1905, the focus has been directed also towards the royal family.
Traditional Norwegian costumes
In Norway, it is common to wear bunad at various celebrations such as: folk dances, weddings, and especially the May 17 National Day celebrations.
In recent years, its use has reached far outside folk dancing, folk music, and particular holidays. Accepted as proper gala attire, it is increasingly common to see people, and especially women, dressed in bunad.
Bunads were also conspicuous among those present at the Blessing of the Reign of King Harald and Queen Sonja, demonstrating that the bunad is now considered acceptable as an alternative form of formal wear even on the most solemn public occasions.
Moreover, people tend to wear bunads to festive celebrations such as anniversaries and birthdays, and for religious occasions including baptisms, confirmations and Christmas.
More here. What you see in the video is the traditional bunad from Hallingdal.