As Lord President of the Council, she was responsible for bearing the Sword of State and presenting the Jewelled Sword of Offering to the King – the first time the role has been carried out by a woman.
Her performance and stamina during the highly visible role won praise across the political spectrum, as well as from audiences watching at home.
“I think you want to make sure you’re in good nick and I did take a couple of painkillers beforehand just to make sure I was going to be all right," the 50-year-old told BBC broadcaster Nick Robinson on his Political Thinking podcast, adding she was "not in the gym for six months" before the event.
“We got through it and it was only half of the ceremony I had to carry the Sword of State, which is the really heavy one, and then I traded it in for the very exquisite Jewelled Sword of Offering, which is much lighter.”
Ms Mordaunt also offered tips for anyone hoping to emulate her achievement.
She said: “I think it’s practice, like anything you’re preparing for, don’t leave anything to chance."
"Have a good breakfast, wear comfortable shoes."
"I had a great team with me because the chaps who haven’t got any plaudits at all, the former defence chiefs who were standing behind me with the other swords in the ceremony, we were all there supporting each other and we’d obviously been talking under our breath at each other during rehearsals, keeping each other going."
Ms Mordaunt commented on the reception she received after the service: "I was reunited with my phone and found I had become a meme."
She also addressed the social media users who likened her outfit to Star Wars' Princess Leia, saying: "That's not the look I was going for."
Ms Mordaunt, the Leader of the House of Commons and a former Conservative leadership frontrunner, carried the 17th-century Sword of State in procession to the abbey.
She later exchanged the Sword of State for the Jewelled Sword of Offering and delivered it to the Archbishop of Canterbury.
The second sword was briefly clipped to the King’s coronation sword belt and then, after a proclamation by the archbishop, Charles stepped forward and offered up the sword.
It was then placed on the altar and redeemed with “redemption money” by Ms Mordaunt.
The sword was later drawn from its scabbard and she carried it in its “naked” form before the King for the rest of the service.
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