Capturing Kahanamoku: How a Surfing Legend and a Scientific Obsession Redefined Race and Culture

by Michael Rossi

The fascinating untold story of one scientist’s pursuit of a legendary surfer in his quest to define human nature, for readers of Why Fish Don’t Exist and Lost City of Z.  

Deep in the archives of the American Museum of Natural History in New York sits a wardrobe of heads—some fifty plaster casts of human faces a century old. How they came to be is the story of one of the most consequential, and yet least-known, encounters in the history of science.  

In 1919, the museum’s then-director Henry Fairfield Osborn traveled to Hawaii for a surfing lesson. His teacher was Duke Kahanamoku, a famous surf-rider and budding movie star. For Osborn, a fervent eugenicist, Kahanamoku was a maddening physically “perfect,” and yet belonging to a notionally “imperfect” race. 

Upon his return to New York, Osborn’s fixation grew. He dispatched young scientist Louis Sullivan to Honolulu with an odd task—to measure, photograph, and cast in plaster the Hawaiian people, Kahanamoku in particular. This outlandish assignment touched off a series of events that forever changed how we think about race, culture, science, and the essence of humanity. 

In Capturing Kahanamoku, historian Michael Rossi draws on archival research and firsthand interviews to weave together a truly fascinating narrative—at once an absorbing account of obsession, a cautionary tale about the subjectivity of science and the afterlives of eugenics, a meditation on humanity, and the story of a man whose personhood shunned classification.  

Genres: History, Nonfiction, Biography, Science

352 pages, Hardcover

Published October 21, 2025

About the author

Michael Rossi is a historian of science and medicine at the University of Chicago and the author of The Republic of Color: Science, Perception, and the Making of Modern America, He has written for the London Review of Books, Nature, the Los Angeles Review of Books, and Cabinet, among other publications. At the University of Chicago, Rossi is a member of the History Department, the Committee on Historical and Conceptual Studies of Science, and the MacLean Center for Medical Ethics. He lives in Chicago and New York.

Reviews

[Ka'i NeSmith · Rating 1 out of 5]

This is disgusting… me he mea la aohe kanaka hawaiʻi e heluhelu ana ai… It’s actually a biography if white men slobbering over Hawaiians. Totally demeaning and objectifying.

[Matt · Rating 3 out of 5]

Well written but much less Duke/surf history than I expected. Still plenty thrilling!

[SundayAtDusk · Rating 5 out of 5]

This book is probably the most painless way a reader can learn about eugenics. That’s because only parts of it is on that topic. The rest is on the history of Hawaii, surfing, swimming, beach boys and Duke Kahanamoku. Author Michael Rossi does an excellent job of interweaving the two main topics, so readers preferring one topic over the other will likely not feel the book is bogging down at any point.

Let’s get eugenics out of the way first, though. The way author Mr. Rossi covers it may not be like some would wish. He doesn’t concentrate on the horrors of practices like forced sterilization that were conducted in the United States, but instead focuses more on those who supported it, and on why they supported it. There’s also plenty of anthropology thrown in, such as how casts were made of the faces of those belonging to different cultures, and how the cast of David Kahanamoku’s body was made.

It was when the Nazis started showing great interest in the eugenics movement in the United States that eugenic beliefs started biting the dust. How horrible what the Germans were doing! What sort of people would believe and support the practice of such things? Eventually, eugenics was seen as nothing but a pseudoscience that never should have been seriously studied in the first place. It disregarded the importance of culturalization and the existence of individuality. Moreover, it was actually rooted in mysticism!

Moving right along . . . this book was a fun, educational read about Hawaii and surfing. Lots of Hawaiian history in general is provided, as well as surfing history. Surfing was originally a well-embraced activity by both men and women. After the missionaries arrived, though, it would sadly become mostly a men’s sport. With the constant arrival of tourists during the 1900, many Hawaiian men soon became part-time or full-time beach boys. The beach boys taught the tourists about surfing and swimming, as well as entertained and educated them in other Hawaiian ways. Both Mark Twain and Jack London tried surfing when visiting Hawaii.

The most famous beach boy and surfer was Duke Kahanamoku, a native Hawaiian who would also go on to win five Olympic medals in swimming. Only when Johnny Weissmuller came along did his glory days of competitive swimming end. Mr. Kahanamoku caught the attention of those preaching eugenics early on due to his powerful body and Hawaiian bloodline. They wanted to do a full-body cast of him, but he wasn’t available at the time, so his brother David took his place. Unfortunately for David Kahanamoku, the plaster was put on and then everyone went for a long lunch, leaving him in increasing physical distress. He survived, but his brother refused to have a cast made after that incident.

When his Olympic swimming days were over, Duke Kahanamoku would go on to give swimming and surfing exhibitions in various countries, making his name synonymous with surfing. He was even in some Hollywood movies, but always returned to Hawaii, the place of his birth and death. While a full-body cast could have captured his magnificent body, it would not have captured his personality, morality, spirit and soul. All so much more important than the shell encasing those things.

(Note: I received a free ARC of this book from NetGalley and the publisher or author.)

[Kathleen M · Rating 2 out of 5]

I was really interested at what I thought was the premise of this book, which is how in the world did white eugenicists latch on to non-white Duke Kahanamoku and his brothers, godlike as they were, as an example of the human ideal? How did white supremacy align with the "scientific obsession" for these Polynesian men? As lengthy as this book was, I didn't get a robust answer. I understand that the Kahanamokus were seen as a magnificent example of "pure race" humans, and their very existence compared to Hawaiians who were of mixed Polynesian heritage was showcased as a type of warning bell to other cultures about the "inferior" offspring that "blood mixing" would produce. But, as other reviewers noted, this wasn't a very deep dive into eugenics. There's no mention of whether eugenicists found (or looked for) superlative types in other non-white races, and the very direct question of how white supremacists, truly, could have genuinely idealized a non-white race or culture was not addressed. It seems like this book has one foot in Hawaiian surf history, and one in eugenics, but goes only knee-deep in both of them.

(Another thing I didn't like is this book doesn't have an index, and the footnotes are super brief to the point of being unhelpful.)

[Relena_reads · Rating 5 out of 5]

Sometimes an author finds the perfect lens to illuminate a major concept, and this is one of those books. Duke Kahanamoku is a legend in his own right and his story really deserves to be more widely known, but he and his brother David were also sought out by eugenicists to prove their theories and Rossi uses their fascinating lives to explain how that period of American and social science history unfurled. In the current moment, when we're being absolutely haunted by the poltergeist that was born of the eugenicist era, this is an especially important book.

It was a bit disconcerting to have a native Hawaiian narrator for a book written by a haole scientist, but Kaleo Griffith is a fantastic narrator.

Thank you to NetGalley for the audioARC.

[David Jonescu · Rating 5 out of 5]

When I received this book, I was expecting a different kind of book but overall this was an interesting book. A great look at the way that the white society viewed the other and how the science of the time viewed bodies and humanity. Although there wasn’t as much Duke or surfing, found the history bits in Hawaii or eugenics and other science fields interesting. Overall good books!

I received a free advanced copy of this book through NetGalley in exchange for an honest review.

[Kuan · Rating 4 out of 5]

Fun story about the eugenic history. Was mostly interested because of the premist that the surfing history was interwoven with the book.