It was meant to be a big family reunion - but the Queen sadly had to pull out of the service of thanksgiving for her 70-year reign.
But it is still significant for others - especially the Duke and Duchess of Sussex who have flown in from the UK especially.
The event marks the first time that the couple has been surrounded by so many members of the Royal Family since their wedding at Windsor Castle in May 2018.
Notably, it is the first time Meghan and Kate have been pictured together since the Duchess of Sussex claimed her sister-in-law made her cry in an interview with Oprah.
Meghan, dressed in cream, could be seen smiling at the crowds gathered outside, who cheered, before Kate, wearing a yellow Emilia Wickstead dress, walked up the steps.
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The royals sat then took their seats inside the building, with the Sussexes in the second row of the congregation next to Princess Beatrice and Eugenie.
Prince Harry looked in jubilant spirits with Princess Eugenie and Beatrice seeming to enjoy their cousin's company.
He could be seen looking relaxed in the pews, as she shared a joke with Eugenie's husband Jack Brooksbank.
Previously, Eugenie made a public visit to Prince Harry in California earlier this year - with the pair said to share a close bond.
Harry and Meghan had to squeeze past his cousins Beatrice and her husband Edoardo Mapelli Mozzi, and Eugenie and her husband Jack Brooksbank, who were already seated, to get to their places.
Harry was spotted giggline alongside Brooksbank - with fans delighting at the moment during the historic service
Beatrice, sitting a few seats down, could also be seen grinning in the same direction.
Meanwhile, Meghan could be seen to chatting to Lady Sarah Chatto, the Queen's niece.
Royal watchers were delighted, with one tweeting: "It’s good to see these two smiling."
The Palace announced last night that the Queen had suffered "discomfort" during the Trooping the Colour, while Prince Andrew ducked out after saying he had tested positive for Covid.
There were smiles from the Earl and Countess of Wessex as the Archbishop of York referred to the Queen’s love of horse racing, while the Princess Royal nodded her head in approval.
The Most Rev Stephen Cottrell told the congregation: “I don’t have any great tips for the Derby tomorrow, but since the scriptures describe life as a race set before us, let me observe that her long reign reflects the distance of Aintree more than the sprints of Epsom.
“Certainly, less dressage than most people imagine.
“But with endurance, through times of change and challenge, joy and sorrow, she continues to offer herself in the service of our country and the commonwealth.
“Your Majesty, we’re sorry you’re not with us this morning in person, but you are still in the saddle. And we are all glad that there is still more to come.”
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