Duke Paoa Kahinu Mokoe Hulikohola Kahanamoku (August 24, 1890 – January 22, 1968) was a Hawaiian competition swimmer, lifeguard, and popularizer of the sport of surfing.

[5] According to Kahanamoku, he was born in Honolulu at Haleʻākala, the home of Bernice Pauahi Bishop, which was later converted into the Arlington Hotel.

[6] He was born into a family of Native Hawaiians headed by Duke Halapu Kahanamoku and Julia Paʻakonia Lonokahikina Paoa.

His mother Julia Paʻakonia Lonokahikina Paoa was a deeply religious woman with a strong sense of family ancestry.

The Kahanamoku and the Paoa ohana were considered to be lower-ranking nobles, who were in service to the aliʻi nui, or royalty.

[9] Growing up on the outskirts of Waikiki, Kahanamoku spent much of his youth at the beach, where he developed his surfing and swimming skills.

During the 1920 Olympics in Antwerp, Kahanamoku won gold medals in both the 100 meters (bettering fellow Hawaiian Pua Kealoha) and in the relay.

He finished the 100 meters with a silver medal during the 1924 Olympics in Paris, with the gold going to Johnny Weissmuller and the bronze to Kahanamoku's brother, Samuel.

[11] The board that Kahanamoku built from a piece of pine from a local hardware store is retained by the Freshwater Surf Life Saving Club.

Kahanamoku was involved with the Los Angeles Athletic Club, acting as a lifeguard and competing in both swimming and water polo teams.

While living in Newport Beach, California, on June 14, 1925, Kahanamoku rescued eight men from a fishing vessel that capsized in heavy surf while it was attempting to enter the city's harbor.

[13] Using his surfboard, Kahanamoku made repeated trips from shore to the capsized ship, and helped rescue several people.

At the time the Newport Beach police chief called Kahanamoku's efforts "The most superhuman surfboard rescue act the world has ever seen."

In the postwar period, Kahanamoku appeared in a number of television programs and films, including Mister Roberts (1955).

While Kahanamoku was a military police officer during World War II, he arrested Duncan, a civilian shipfitter, for public intoxication.

[16] On August 2, 1940, Kahanamoku married dance instructor Nadine Alexander, who had relocated to Hawaii from Cleveland, Ohio, after she had been hired to teach at the Royal Hawaiian Hotel.

[23] For his burial at sea, a long motorcade of mourners, accompanied by a 30-man police escort, traveled in procession across town to Waikiki Beach.

A group of beach boys sang Hawaiian songs, including "Aloha Oe", and Kahanamoku's ashes were scattered into the ocean.

[26] In April 2022, NSW Heritage announced that Kahanamoku would be included in the first batch of Blue Plaques to be issued, to recognize his contribution to recreation and surfing.

The Duke Kahanamoku Aquatic Complex (DKAC) serves as the home for the University of Hawai‘i's swimming and diving and women's water polo teams.