Luxembourg's national holiday is celebrated every year on June 23rd.
Since the end of the 18th century, it has been a tradition to celebrate the birthday of the respective ruler.
Although William III was born on February 19, this holiday was moved in 1850 to June 17, the birthday of his wife, Queen Sophie. Under Grand Duchess Charlotte, the celebration fell on January 23, in the middle of winter. Therefore, in 1961, it was decided to celebrate the Grand Duchess's birthday on June 23 due to the more favorable weather. This date was retained when Grand Duke Jean ascended the throne on November 12, 1964.
The date was chosen – presumably because it was the day before his name day, John (Jean), which is celebrated on June 24th as Gehaansdag. The date remains in use under the current Grand Duke Henri, but no longer has a direct connection to the monarch. Nevertheless, the national holiday in Luxembourg is often referred to as the Grand Duke's Birthday.
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