Charles Spencer shared a fabulous photo to social media on Wednesday.
Princess Diana's brother uploaded a sepia picture showing one of his ancestors' close family members, Admiral Sir Beauchamp Seymour.
It showed the senior officer wearing his navy uniform as he sat on a low wall, with one foot on the floor and one lifted a little bit off the ground.
He had a very dignified expression as he looked to one side and also boasted a luxuriant head of hair, with incredible sideburns that grew as far as his chin.
The Earl captioned the rare image: "This wonderful, swaggering figure was brother-in-law to the 5th Earl Spencer.
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"A leading light in the Victorian Royal Navy, commanding the Channel and the Mediterranean fleets, Admiral Sir Beauchamp Seymour was known as 'the Ocean Swell.'"
Fans loved Charles' long-ago relative's look, with one replying: "He certainly looks debonair, and what a great name 'The Ocean Swell.'"
Many of the 56-year-old's followers couldn't resist commenting on his facial hair, with their responses including: "Magnificent sideburns," and "Those are some impressive sideburns."
Another joked: "You forgot to mention that it was this man who gave Noddy Holder of Slade the inspiration for his sideburns."
Charles shared the remarkable image to Twitter
A fourth, meanwhile, teased: "Everyone below seems to be referring to the facial hair as sideburns, but I think the correct contemporary term is mutton chops. I dare you to try that look out if we have another lockdown, Charles!"
This isn't the first time that Charles has impressed his social media followers with a family portrait.
Just last month, he shared a snapshot which showed the hallway and stairs of his family home, Althorp House, where several paintings of his loved ones could be seen.
They included a picture of his wife Karen, who he married in 2011, and one of his sister.
Charles and Diana, Princess of Wales grew up on the lavish estate, and he is now custodian of the house and its grounds, where the late Princess was laid to rest.
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