The special event took place in the Quadrangle at Windsor Castle, where the Queen has been isolating with 99-year-old Prince Philip.
The royal event was broadcast on the BBC with commentator Huw Edwards saying: “If you’re lucky, you’ll catch the twinkle in Her Majesty’s eye” as the Queen looked on at the guards.
The guards had to maintain a two-metre distance at all times, while music played by a Band of the Household Division.
The Queen wore a special brooch with a hidden meaning in a nod to the Welsh guards who performed the march.
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Wearing a mint green suit and hat, the Queen accessorised her turquoise outfit with a diamond brooch that held a special meaning for the guards.
The Queen always wears the same brooch each year for the Trooping the Colour celebrations, the Guards’ Badge.
The Grenadier Guards badge features a leek for the Welsh Guards, with the Scots Guards’ badge (a thistle) on the left, Coldstream (St George’s Cross) at the bottom and Irish on the right (shamrock).
However, as a tribute to the Welsh guards who performed the unique ceremony for today, the Queen wore a different brooch – a diamond leek on its own.
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The significant brooch replaced her usual uards’ adge for the unusual occasion, which due to the lockdown had to be very different to the usual ceremony that had been planned.
The leek is widely recognised as the national symbol of Wales, and so was carefully chosen to honour the regiment trooping their colour.
The meaningful symbol dates back as far as the Elizabethan times, with Shakespeare referring to the custom of wearing a leek as an “ancient tradition”.
The Queen’s green coat was designed by Stewart Parvin, as well as the floral silk dress underneath which featured green and pink shades.
The Queen wore a matching hat for the official event, created by Rachel Trevor-Morgan, a floral and ribbon design.
Dressed formally for the birthday event, the Queen also wore her signature pearl necklace, and a pair of pearl earrings to finish look.
The royal as she watched from the sidelines,
The BBC commentators said it was nice to see the monarch showing her support for the guards with the particular choice of the leek brooch.
Though usually the full Royal Family would be out in force for the annual event, the brief ceremony was a much smaller affair due to the lockdown rules.
However, it’s thought that the family will have tuned in to watch the event from their homes around the country.
The Welsh guards have also had an important role to play in recent months in helping to battle the pandemic.
A clip in the BBC coverage revealed that they had been manning Covid-19 test centres as part of the nation’s response to the virus, making their performance today particularly poignant.