In my headcanon, Albert Campion's real last name is Blakeney

So, Albert Campion is a fictional gentleman detective/adventurer, created by Margery Allingham, in stories she wrote from 1929 to 1965. He makes no secret that "Albert Campion" is a pseudonym, and that he comes from a privileged background.

So I think it's clear that he's the descendant of Sir Percy Blakeney, also known as The Scarlet Pimpernel.

He probably knows Bertie Woodhouse, too. I'm sure that Lugg and Jeeves have traded tips on valeting. (Magersfontein Lugg is Campion's manservant. He's not a very good servant, but he's an excellent burglar and good with his fists.)