Among the esteemed guests were US President Donald Trump and his wife Melania Trump, who visited the UK this week.
The President and the First Lady (FLOTUS) were joined by Theresa May, as well as French President Emanuel Macron and his wife, Brigitte.
But FLOTUS courted controversy for donning sunglasses throughout the event, with some questioning her decision not to remove them as a mark of respect.
One Twitter user said: “Melania wearing sunglasses.
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“Not appropriate at these ceremonies.”
Someone else penned: “Melania needs to take the dang sunglasses off. It’s rude!
“Yes, I’m a little old fashioned.”
Meanwhile another person pondered: “Why did Melania Trump not remove her sunglasses at this most solemn D-Day ceremony?
“Mrs Macron wasn’t wearing sunglasses.
“I guess she is uncomfortable making eye contact.
“She thinks she is sitting on the French Riviera sipping champagne!”
And someone else simply wrote: “Melania needs to take off her damn sunglasses.”
But not everyone was so scathing.
A supporter of the First Lady wrote: “Mrs Trump, your words and actions humble me. God bless you.”
And another penned: “Thank God for this spectacular extra special First Lady!”
Mrs Trump is no stranger to controversy when it comes to her fashion choices.
She once wore a jacket with the words ‘I really don’t care, do you’ emblazoned on the back when she was going to visit a Texas immigration centre.
She also raised eyebrows when she chose to wear a colonial-style hat in Kenya, and more recently when she wore a dress printed with London attractions during a three-day trip to the UK this week.