It’s one of those questions that pops up at trivia nights or during late-night Wikipedia rabbit holes: were Franklin and Eleanor Roosevelt cousins? The short answer is a flat "yes." But honestly, the long answer is way more interesting than just a family tree connection. We’re talking about a marriage that redefined the American presidency, born out of a social circle so small and elite that finding a spouse who wasn't some kind of relative was actually the harder task.
They weren't brother and sister. Let's get that out of the way first. They were fifth cousins once removed. If you're scratching your head trying to do the math on that, don't worry. Most people can't track their family back to their great-grandparents, let alone a fifth cousin. In the world of the New York "Knickerbocker" elite at the turn of the 20th century, this was basically like marrying a distant acquaintance who happened to share your last name.
The Family Tree Logic
To understand how this worked, you have to look at the two distinct branches of the Roosevelt family: the Hyde Park Roosevelts and the Oyster Bay Roosevelts. Franklin Delano Roosevelt (FDR) hailed from the Hyde Park side—the wealthy, landed gentry of the Hudson Valley. Eleanor belonged to the Oyster Bay branch, which most famously produced her uncle, Teddy Roosevelt.
Their common ancestor was a guy named Nicholas Roosevelt, who lived way back in the late 1600s. Nicholas had two sons, Johannes and Jacobus. From Johannes came the Oyster Bay (Eleanor/Teddy) line. From Jacobus came the Hyde Park (Franklin) line. By the time Franklin and Eleanor met as adults, they were several generations apart.
Interestingly, Eleanor was a Roosevelt by birth. When she married Franklin, she didn't even have to change her last name. At their wedding on St. Patrick’s Day in 1905, President Theodore Roosevelt walked his niece down the aisle. He reportedly joked to Franklin, "Well, Franklin, there's nothing like keeping the name in the family."
Why the Roosevelt Connection Still Fascinates Us
People get weirded out by the "cousin" label today, but back then, among the 400 wealthiest families in New York, it was standard operating procedure. They all went to the same balls, stayed at the same summer estates, and attended the same Ivy League schools.
The social geography of their world was tiny.
Franklin was a dashing, somewhat pampered only child. Eleanor was the "ugly duckling" of her family—serious, orphaned at a young age, and deeply soulful. They met on a train in 1902. He was a Harvard student; she was a debutante just returning from schooling in England. They talked. They really talked. Franklin was captivated by her intellect and her depth, which stood in stark contrast to the flighty socialites he usually encountered.
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The Sara Delano Factor
If there was any real drama regarding their relationship, it wasn't about them being cousins. It was about Franklin’s mother, Sara Delano Roosevelt. Sara was the definition of a "smother-mother." She was wealthy, controlling, and absolutely certain that no woman was good enough for her "Franklin boy."
She actually tried to break them up.
When Franklin announced he wanted to marry Eleanor, Sara was devastated. She took him on a Caribbean cruise specifically to try and make him forget her. It didn't work. Franklin was stubborn, and Eleanor was his match. They married anyway, though Sara famously moved into a townhouse right next door to them in New York City, with connecting doors on every floor so she could walk in whenever she pleased. Talk about a nightmare mother-in-law situation.
Breaking Down the "Fifth Cousin Once Removed" Math
Let's get technical for a second because "fifth cousin once removed" sounds like a math equation nobody asked for.
- Fifth Cousins: This means they shared a set of great-great-great-great-grandparents.
- Once Removed: This means they were from different generations. Specifically, Franklin was in the same generational "tier" as Eleanor’s father, Elliott.
In terms of genetics? It’s negligible. You share about 0.05% of your DNA with a fifth cousin. You probably share more DNA with a random person in your zip code than Franklin and Eleanor shared through their Roosevelt lineage. The concern about "inbreeding" that people often associate with historical royal families doesn't apply here. This wasn't the Habsburgs. It was just two people from the same massive, sprawling clan finding each other in a small social pond.
A Marriage of Politics and Pain
Their relationship wasn't some fairy tale. While they were "cousins," they ended up being more like political partners than a traditional romantic couple for much of their lives.
In 1918, Eleanor discovered a packet of love letters in Franklin’s luggage. He had been having an affair with her social secretary, Lucy Mercer. It shattered Eleanor. She offered him a divorce, but Sara (the mother-in-law) stepped in and threatened to cut Franklin off financially if he left his wife. Also, a divorce back then would have ended Franklin's political career instantly.
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They stayed together. But the marriage changed.
Eleanor grew into her own person. She became a fierce advocate for civil rights, women's rights, and the poor. When Franklin was struck by polio in 1921, Eleanor was the one who kept his political name alive, traveling the country because he couldn't. They became the most formidable political duo in history. He was the charm and the policy; she was the conscience and the boots on the ground.
The Oyster Bay vs. Hyde Park Rivalry
You might think the two Roosevelt branches were one big happy family, but there was a ton of friction. The Oyster Bay Roosevelts were mostly Republicans. The Hyde Park Roosevelts (Franklin) were Democrats.
Alice Roosevelt Longworth, Teddy’s daughter and Eleanor’s first cousin, was famously wicked with her tongue. She once described Franklin as "one-third mush and two-thirds Roosevelt." She spent years mocking their branch of the family, even though she and Eleanor had grown up together.
This family dynamic is crucial because it shows that being "cousins" didn't mean they were a monolithic unit. They were competing for the same legacy. When Franklin ran for president, some of the Oyster Bay Roosevelts actually campaigned against him.
What People Get Wrong About the Scandal
Modern readers often look at the Roosevelt marriage through a 21st-century lens of "ew, they were related." But in 1905, the "scandal" wasn't the kinship. The scandal was the power dynamic.
Eleanor was seen as a "plain" girl who had landed the most eligible bachelor in New York. Later, the scandal was their unconventional living arrangements. By the time they reached the White House, they often lived largely separate lives. Eleanor had her own circle of friends at Val-Kill, her cottage in Hyde Park, while Franklin had his "inner circle" in the West Wing.
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They respected each other immensely, but the romantic spark had largely been replaced by a shared mission to save the country from the Great Depression and later, the Nazis.
The Genetic Legacy
Did their being cousins affect their children? Not really. They had six children (one died in infancy), and all grew to adulthood. While many of the Roosevelt children had tumultuous personal lives—lots of divorces and career shifts—there were no "genetic" issues stemming from their parents' distant relation.
The Roosevelt kids were:
- Anna: A journalist and aide to her father.
- James: A Marine Corps officer and Congressman.
- Elliott: An author and aviation officer.
- Franklin Jr.: A lawyer and politician.
- John: A businessman.
They were all high-achieving, intense individuals, much like their parents and their "Uncle Teddy."
How to Verify Historical Lineage Yourself
If you’re researching famous families and trying to figure out if people are related, don't just trust a single family tree site.
- Check the Common Ancestor: Always look for the "progenitor." For the Roosevelts, it’s always Nicholas or Claes Martenszen van Rosenvelt.
- Look for "Double Cousins": Sometimes families intermarry multiple times across generations. This wasn't the case with FDR and Eleanor, but it happens in other dynasties.
- Read the Memoirs: Eleanor’s autobiography, This Is My Story, gives a very candid look at how she viewed her family and her marriage. She doesn't focus on the "cousin" aspect because, to her, it was the least interesting thing about her life.
Lessons from the Roosevelt Union
The story of Franklin and Eleanor reminds us that history is messy. We like to put historical figures in neat boxes, but they were real people navigating complex family traditions.
Takeaways for History Buffs:
- Kinship in the early 20th century was a tool for social consolidation.
- "Fifth cousin" is a very distant relation, practically a stranger in genetic terms.
- The Roosevelt marriage was a partnership of necessity and mutual respect that transcended their family ties.
- Public perception of "appropriateness" changes wildly over a century.
If you want to dive deeper into this, I highly recommend visiting the FDR Presidential Library and Museum in Hyde Park. You can literally see the two townhouses Franklin’s mother built—one for her and one for the couple. Seeing those shared walls makes you realize that the real "closeness" in their marriage wasn't because they were cousins; it was because they were constantly under the watchful eye of a very formidable matriarch.
Next Steps for Your Research:
- Search for the "Oyster Bay vs. Hyde Park" political split to see how the family feuded during the 1932 election.
- Look up the letters between FDR and Eleanor during their courtship—they are surprisingly sweet and reveal a genuine connection that had nothing to do with their last name.
- Examine the guest list of their 1905 wedding to see the "Who's Who" of the Gilded Age.