In many cultures around the world, it is frowned upon to marry your cousin (and in some countries even illegal), but that hasn’t stopped people throughout history from doing it.

From presidents like Martin Van Buren and John Adams to royals like Queen Victoria and Prince Albert, historical figures have often engaged in this practice. But there are even a few more modern examples (and some legendary ones) where couples have opted to wed within their own familial bloodlines. Maybe your own family tree has a few kissing cousins on its branches!

Rudy Giuliani. The former mayor of New York City married Regina Peruggi in 1968. Regina was the daughter of his father’s first cousin, making her his second cousin once removed. Giuliani filed for an annulment in 1982 to end their marriage after 14 years.

Edgar Allan Poe. For his second marriage, the famed poet and author of “The Raven” wed his first cousin Virginia Eliza Clemm. The two were married when he was 27 and she was 13. There is some speculation as to whether their marriage was more like a sibling relationship than that of husband and wife.

H.G. Wells. Author of “Island of Dr. Moreau” and “The War of the Worlds,” Wells married his first cousin in 1891. But their union was short-lived, and he and Isabel Mary Wells divorced a mere three years later when he began a relationship with one of his students.

Saddam Hussein. The former Iraqi dictator had multiple wives, but his first wife was his first cousin, Sajida Talfah, whom he married in 1963. Their pairing was an arranged marriage, planned from the time the two were children.

Charles Darwin. The naturalist who penned “On the Origin of Species” — and introduced the theory of evolution to the world — married his first cousin Emma Wedgwood. The couple had 10 children together, and because of his research on inbreeding and evolution, he was worried that their relationship was the reason that three of their children died at young ages.

Albert Einstein. Famed physicist Albert Einstein married his second wife, Elsa Lowenthal, in 1919 in one of the oddest cousin pairings ever. They were first cousins on his mother’s side, as well as second cousins on their father’s side! And weirder still, she was actually born Elsa Einstein; the Lowenthal surname was one she got from her first marriage.

Jerry Lee Lewis. The rocker best known for his hit song “Great Balls of Fire” married his first cousin Myra Williams when she was only 13 years old. The union, which was his third marriage and her first, caused a lot of fan backlash for Lewis, and the pairing lasted only four years. He would go on to marry four more times.

Greta Scacchi. The actress known for her starring role in “Presumed Innocent” was once married to Vincent D’Onofrio. They weren’t related and have since divorced; now, Scacchi is in a long-term relationship with her cousin Carlo Mantegazza, and the two have a child together.

Kevin Bacon. Many people claim to have connections with Kevin Bacon — there’s that whole “Six Degrees of Kevin Bacon” game — but his wife, Kyra Sedgwick, is actually related to him … albeit quite distantly. The two are ninth cousins once removed, a fact they learned on the PBS genealogy series “Finding Your Roots.”

Jesse James. The notorious outlaw fell in love with and married his first cousin Zerelda “Zee” Mimms. She was actually named for Jesse’s mother, and the two finally wed after a nine-year engagement and had two children who survived.

Are there any married cousins back on a branch of your family tree? Start investigating today with a free trial from Ancestry.

— Angel Cohn