That makes sense. But then I wonder why there hasn't been any Belgian State Visits to the UK for such a long time.
No State Visits between Queen Elizabeth II and King Albert II or King Philip. The same goes for Grand Duke Henri.
As you say, both the current and Dutch and Spanish Monarchs and their predecessors have been given the Garter, but neither King Albert II, nor King Philippe of the Belgians have been bestowed with that honour. I wonder why.
GARTER DAY AT WINDSOR CASTLE
Monday 17th June 2019
A service for the Most Noble Order of the Garter will be held in St George’s Chapel, Windsor Castle, on Monday 17th June 2019. The installation of the new Garter Knights and Supernumerary Knights will take place during this service. Following the service, the Queen and members of the Royal Family will depart by carriages for their return journey to the castle.
Earlier in the day, there will be a private Investiture in the Garter Throne Room, Windsor Castle, where a Lady Companion, Lady Mary Peters, and a Knight Companion, the Marquess of Salisbury, will be invested with the order's insignia by Her Majesty.
The King of Spain and the King of the Netherlands will also attend this year’s Garter Day, during which they will be installed in St. George’s Chapel as Supernumerary, or ‘Stranger’, Knights of the Garter.
The King of Spain was appointed by Her Majesty on the occasion of the Spanish state visit in July 2017, and the King of the Netherlands was appointed on the occasion of the Netherlands state visit in October 2018 .
The Queen of Spain and the Queen of the Netherlands will also be in attendance and will join the carriage procession.
Background
The Order of the Garter is the oldest and most senior Order of Chivalry in Britain, established by King Edward III nearly 700 years ago. The Order includes the Queen, who is Sovereign of the Garter, several senior members of the Royal Family, and twenty-four knights or ladies chosen in recognition of their work. Knights of the Garter are chosen personally by the Sovereign to honour those who have held public office, who have contributed in a particular way to national life or who have served the Sovereign personally.
Supernumerary, or ‘Stranger’ Knights, are overseas monarchs appointed to the Order, and are in addition to the twenty-four knights or ladies. Princess (formerly Queen) Beatrix of the Netherlands was made a member of the Order in 1989. The former King Juan Carlos of Spain was also given the Order in 1988.
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