The Princess wore a deep green gown by Andrew Gn for tonight’s state dinner honoring the President of Nigeria, Bola Ahmed Tinubu, and First Lady Oluremi Tinubu. 
The banquet was held at St. George’s Hall at Windsor Castle due to the extensive remodeling and refurbishment project at Buckingham Palace. Below is a photo of the King, Queen, President Tinubu, and the First Lady. 
The Duke of Edinburgh, Princess, and Prince William. 
The Duchess of Edinburgh wasn’t in attendance tonight. I do know she has been traveling quite a bit, most recently to New York and Italy.
In this image, you can see the Princess Royal on the right, and her husband, Vice Admiral Sir Tim Laurence, seen on the left. You can just make out the Duchess of Gloucester. 
The King, Queen, and guests of honor as they walked into dinner.
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Prince William and a guest, whom I was unable to identify. 
The Princess Royal and Sir Tim.
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The Duke and Duchess of Gloucester.
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A brief video showing their walk into St. George’s Hall.
Her Royal Highness Princess Anne, The Princess Royal and her husband, Vice Admiral Sir Tim Laurence, attending the Nigerian State Banquet at Windsor Castle, this evening! ✨👑♥️ pic.twitter.com/0jyBc1vsgm
— Princess Anne & Sir Tim Laurence ✨ (@TheLaurences_) March 18, 2026
More on tonight’s dinner from ITV’s coverage:
Mr Tinubu’s stay is the first incoming state visit by a Muslim leader during Ramadan since 1928 when King George V hosted King Amanullah Khan of Afghanistan.
The President broke his fast privately at sunset before joining the Royal Family for the banquet. The First Lady is a Christian and an ordained Pentecostal pastor.
For the first time in living memory, canapes were offered ahead of the dinner to offer sustenance to Muslim guests who were unable to partake in iftar – the breaking of their fast.
Here, you get a sense of the massive table in the hall, which measures more than 150 feet; more than 140 candles were used for the dinner. 
More about the preparations and the flowers from this People story.
Palace staff started work setting up the table on Sunday and continued to make preparations until shortly before the dinner began. Among the last things to be added were the magnificent flower arrangements using blooms from the gardens at Buckingham Palace, Windsor Castle, and the Savill Garden in Windsor. Any flowers that cannot be reused after the banquet will be donated to Floral Angels, Queen Camilla’s patronage, which delivers flowers to hospices, elderly care homes, shelters and more.
In this photo, I believe guests are standing for the countries’ national anthems. 
ITV reports the menu included:
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Soft-boiled quail egg tartlet with watercress, kale, and a basil sabayon
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Filet of turbot, lobster mousse wrapped in spinach, beurre blanc sauce, sprouting broccoli with hollandaise sauce, fricasse of peas and broad beans, Jersey Royal potatoes
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Iced blackcurrant souffle with red fruit coulis
Almost one thousand knives and forks were used for tonight’s table service. 
The Princess laughing with a member of the Nigerian delegation. 
The Daily Mail has details on tonight’s beverages in this article.
English sparkling wine was used for the toasts for those who were drinking alcohol, and the menu did not include meat.
You can see President Tinubu drinking range juice in this photo, and the Princess sipping on water. 
King Charles and President Tinubu delivered remarks. The Telegraph offers more on the King’s speech.
The King’s banquet speech, customarily a mixture of serious diplomacy and jokes, included the “Yoruba wisdom” of “rain does not fall on one roof alone”, the Hausa saying “when the music changes, so does the dance” and the Igbo “knowledge is never complete, two heads are better than one”.
Speaking of a “tea and jollof” reception he hosted at St James’s Palace last week, the King entered the famous debate over which country is home to the best rice dish: “I was firmly assured that the jollof was only the best: Nigerian, of course… or perhaps Ghanaian or Senegalese. Diplomatically, I cannot remember.”
Sky News offers about one minute of the speech in this video.
‘Last week, I was delighted to host a jollof and tea party at St. James’s Palace. I was firmly assured that the jollof was only the best. Nigerian of course.’
King Charles welcomes Nigeria’s President Bola Tinubu at Windsor Castle for his two-day state visit… pic.twitter.com/Dd5TEZS71J
— Sky News (@SkyNews) March 18, 2026
Now, for a quick review of what some royal guests were wearing, beginning with the gentlemen, all of whom sported the formal red Windsor uniform, with its distinctive scarlet collar and cuffs on the jacket.
The Queen was in a cream embroidered gown by Fiona Clare, the late Queen’s Belgian Sapphire Tiara with matching earrings, and a diamond necklace that belonged to her mother.
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Princess Anne wore an evening coat dating back to at least 1969, with thanks to Royal British Fashion for that insight, and a bandeau tiara. The Court Jeweler reports that her earrings were an 18th-birthday gift from her parents.
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The Duchess of Gloucester was in a wonderful shade of deep blue. The Court Jeweller reports she wore Queen Mary’s Iveagh Tiara, with stacked necklaces and bracelets, and diamond clips from a tiara belonging to her mother-in-law. Pop over to TCJ for full details.
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We now turn to our look at what Kate wore. 
Her dress very much looks like a bespoke version of Andrew Gn’s Chiffon Pleated Gown in a bespoke color, with thanks to Laura and UFO No More for a speedy ID.
The 100% silk design is from the designer’s F/W 2021 collection, featuring a high neck, puffed blouson sleeves, pleating at the front neck and all around the waist, and a concealed back zipper. The Princess did not wear the pearl-buckled belt shown with the off-the-rack version of the style. 
As many readers may know, green is one of the two primary colors seen in Nigeria’s flag—more from this GB News story.
The colours carry clear meaning; green represents Nigeria’s rich natural wealth, especially its forests and agriculture, while white symbolises peace and unity.
Middleton Maven connected with the designer online. More from her Instagram post.
Andrew Gn confirms that he created this gown for the Princess of Wales in 2022, before retiring in 2023. He describes it as part of a belief in “heritage design” — beautifully made pieces to be treasured and passed down to the next generation, much like jewelry.
Below, the designer at the conclusion of his 2019 runway show.
More about Mr. Gn from Women’s Wear Daily.
While he’s dressed everyone from Queen Rania of Jordan to Lady Gaga, the genial designer has kept a relatively low public profile so far, preferring to cultivate close personal relationships with his customers. Early in his career, trunk shows introduced him to society doyennes such as Lynn Wyatt, Blaine Trump and Susan Gutfreund.
We first saw her wearing the glittering gems with an Erdem gown for the 2015 100 Women in Hedge Funds dinner.
Born to immigrant parents in Singapore in 1966, Gn (pronounced “gin” with a hard “g”) was encouraged to travel and ultimately studied in Paris, New York City, and Milan before founding his Paris atelier, The House of Andrew Gn, in 1995. What “began simply in his apartment with an assistant and a sewing machine,” Slinkard says, grew into a 28-year business that produced 80 collections and some 10,000 ensembles. One of the few independent fashion houses to succeed financially, the atelier (which closed in 2023) is known for rich ornamentation, impeccable materials, and the artist’s disparate global aesthetic
Making its North American debut, Andrew Gn: Fashioning the World illuminates the designer’s life and legacy, showcasing nearly 100 stunning works, including clothing, accessories, original illustrations and digital media. The experience is divided into thematic sections highlighting the designer’s signature blend of Western aesthetics, art history and Asian decorative art and design.
Ann S
Thursday 19th of March 2026
I wish The Princess of Wales would go back to wearing updos on "tiara occasions". I assume her husband must prefer the way she looks with her hair worn down and she doesn't care what anyone else thinks. Catherine's fashion choices for the Nigerian state visit have been very appropriate, but I don't like this particular shade of green on her. There is a black undertone that washes her complexion out a bit. The design of the gown is very flattering though. I will ask once again if anyone knows why it is that Catherine and Camilla have stopped wearing their Queen Elizabeth II Royal Family Orders. All the other royal ladies who have them manage to wear both their QEII and KCIII Orders without any obvious strain to their left shoulders. I'm unaware of any precedent that would suggest that Camilla's and Catherine's place in seniority accounts for it. The late Queen wore the Orders of both her father and grandfather right up to her final state banquet.
Kay Grant
Thursday 19th of March 2026
The Princess of Wales is always a lovely harmony of elegance and grace. The elegance of personal adornments-her smile, calmness, deportment and comportment are most impressive and aspirational. Brava!
Caro
Thursday 19th of March 2026
I agree with the comments that this is a real miss for Catherine. When I first saw the pictures, I searched for her other deep green dresses and I think every one of them looked better on her than this one did. There was a sequin deep green, the velvet she recently wore, and the Jamaica dress. I would love to see the Jamaica dress again, but if I’m not mistaken, the Princess typically does not rewear dresses for the state dinners, so wearing a dress so different than her other green dresses might have been a way to distinguish guisthis dress and honor their guests. I think there is somewhat similar pink dress that I also feel isn’t flattering on her but I really can’t pinpoint why. Anyway, I would hate to get dressed knowing that the eyes of the world would be scrutinizing me, and even in a dress that I think doesn’t flatter her, I have never looked as good in my life, so I’m not really one to judge.
Jade Hurst Sargeant
Thursday 19th of March 2026
I love this dress, I think it is absolutely gorgeous! It also looks warm and comfortable, which is an added plus! I also love Anne’s ribbed gown.
PeggyL
Thursday 19th of March 2026
I really like the way all the royal ladies coordinated their gowns, and while a bit more modest than they might normally go, the respect they showed to their guests was lovely. The Queen especially wears formal dress so well, she knows so well what suits her, and sticks with it. Katherine's dress was a beautiful color and well fitted, but it did seem to overwhelm her a bit. It does look like it would be fun to wear, though-silk swishes so nicely! I liked the sapphires to match the sash, though her emerald earrings would have been gorgeous.