Meghan wore a stunning tulle dress with a beaded detail and puffed sleeves, while Harry sported black tie.
The duchess accessorised her outfit with gold earrings and a gold bangle, wearing her hair in a stylish bun.
Fans were quick to source the designer gown on social media.
The pair are understood to have jetted into Rome on a commercial flight yesterday without baby Archie for the fairytale wedding.
They joined a string of a-listers, including Katy Perry, Orlando Bloom, Princess Eugenie and Ivanka Trump for the nuptials of their fashion designer friend Ms Nonoo, who is said to have set them up on a blind date in 2016.
Click through the gallery above for more of the celebrity wedding guest outfits.
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