American author Scott O'Dell penned 26 children's novels over the course of his career, but his most popular by far is Island of the Blue Dolphins. The haunting—and at times harrowing—story followed the adventures of a Native American girl forced to survive alone on a forgotten island, where she tamed wild dogs and defied the odds. But as beloved as this book is, few know the incredible true story that lies just beneath O'Dell's spare but thoughtful prose.

1. O'DELL TOOK A LONG ROAD TO WRITING CHILDREN'S NOVELS.

O'Dell got his start in the burgeoning film industry. Before serving in the U.S. Air Force in World War II, he snagged jobs as a cameraman and a technical director, later transitioning to work at the Los Angeles Mirror as a book columnist, then the Los Angeles Daily News as a book editor. Though he'd begun writing articles and novels for adults in his mid-thirties, it wasn't until he was in his sixties that O'Dell found his calling as a children's novelist. By 1972, his incredible works—including Island of the Blue Dolphins, The Black Pearl and Sing Down the Moon—earned him the Hans Christian Andersen Award, the greatest honor offered to children's book creators.

2. ISLAND OF THE BLUE DOLPHINS WAS BASED ON A TRUE STORY.

Though published in 1960, the novel's inspiration came from over 100 years before. Off the coast of California lies San Nicolas Island, where the Nicoleño tribe once thrived. In 1814, a brutal slaughter at the hands of Native Alaskan otter hunters critically hurt the tribe's numbers. By 1835, missionaries intervened, urging the last of the Nicoleño to leave their little island in favor of the more hospitable mainland. But a young woman—who would come to be called Juana Maria—literally missed the boat. She spent 18 years on the island all by herself, and would become remembered as the Lone Woman of San Nicolas Island. O'Dell's version of this story left out the missionaries, but maintained the slaughter by trappers and the tribe's abandonment of the island.

3. ONE KEY DETAIL OF THE LONE WOMAN HAS BEEN LOST TO HISTORY.

No one knows the Lone Woman of San Nicolas Island's real name. "Juana Maria" is what the missionaries christened her when she came to their mission in her 40s. With her real name lost, O'Dell opted to call her fictional doppelgänger Karana.

4. O'DELL INCLUDED A POPULAR BUT UNVERIFIED DETAIL OF THE LONE WOMAN'S TALE.

Why didn't Juana Maria join her people on the boats? The most popular theory is that she did, but as the ship took to the sea, she realized a child (usually her child) had been left behind. So, she dramatically dove overboard to return to and care for it. But Navy archaeologist Steven Schwartz believes this is not the best explanation, as much as the best story. "The story of her jumping overboard does not show up until the 1880s (nearly 50 years after the event)," he says. "By then the Victorian era is well underway, and literature takes on a flowery, even romantic flavor."

Still, the story appealed to O'Dell. In Island of the Blue Dolphins, Karana follows in the mythic footsteps (or swim strokes) of Juana Maria, diving overboard and returning to shore once she realizes her little brother has missed the boat.

5. KARANA WAS MUCH YOUNGER THAN HER REAL-LIFE INSPIRATION

Juana Maria is believed to have been around 24 when she was stranded on San Nicolas Island. (Her exact age cannot be pinned down, because her birth date is unknown.) To raise the stakes and make the story more appealing to the children it was aimed to entertain, O'Dell made the heroine of his novel a tenacious 12-year-old girl.

6. O'DELL DIDN'T RESEARCH MUCH ABOUT THE NICOLEÑO.

Because of how the tribe was killed off and then dispersed into California, the Nicoleño culture has been largely lost. So the 60-something O'Dell looked to the legends and customs of other tribes of the Channel Islands, then carefully described tools like the pitch-lined baskets used to haul water. But as Slate noted in a book review of the novel's 2016 Complete Reader's Edition, "Other details, like the islanders’ use of two names—a public one for strangers and a true one for trusted intimates—he simply made up."

7. THE COMPLETE READER'S EDITION INCLUDED NEW PAGES.

Edited by associate professor of English at the University of South Carolina Sara L. Schwebel, this version of O'Dell's novel boasts two previously excised chapters that had never before been published, as well as "a critical introduction and essays that offer new background on the archaeological, legal, and colonial histories of Native peoples in California." These elements aim to add a greater context and discussion tools for modern readers.

8. ISLAND OF THE BLUE DOLPHINS WAS ADAPTED INTO A MOVIE

The film directed by James B. Clark opened on July 3, 1964, to faint praise. The New York Times's Howard Thompson described it as "a bit thin and sugary," adding, "(Island of the Blue Dolphins) is about as unstartling and uneventful as can be—and as pretty to look at." Nonetheless, ingénue Celia Kaye won a Golden Globe for Most Promising Newcomer (Female), while the film was honored with Boxoffice Magazine's Best Picture of the Month for the Whole Family award.

9. SCOTT O'DELL OFFERED AN ISLAND OF THE BLUE DOLPHINS SEQUEL 16 YEARS LATER.

Zia follows the titular heroine, the 14-year-old niece of Karana, as she sets forth on a sea-faring quest to find her long-lost aunt. After many trials and tribulations, Zia does reunite with Karana, but their joy is short-lived. Upon its release in 1976, Publisher's Weekly called the children's novel "Bound to be among the outstanding books of the year."

10. ZIA ALSO PULLED FROM REAL LIFE.

O'Dell created the character of Zia altogether. But in the book, the girl discovers proof that Karana may still live in that she finds footprints in the sand, the remnants of a cooking fire, and a small hut. In real life, American mountain man/explorer/otter hunter George Nidever led three expeditions to San Nicholas, originally for sea gull eggs. On the first expedition he found a footprint that had been made a long time prior alongside more recent evidence of seal blubber dehydrating. On a second trip they found more evidence of recent occupation, and on the third trip he found the Lone Woman. Another true detail cherry-picked for Zia was that no one could really communicate with Juana Maria, her language having transformed into something unique and unfamiliar to the mainlanders. Plus, just as he did in real life, "Captain Nidever" brings the lost tribeswoman to the mainland, and then to the Santa Barbara Mission.

11. THE LONE WOMAN'S CAVE HAS BEEN DISCOVERED.

Today San Nicolas is predominantly a naval air station, where aforementioned archaeologist Schwartz has dedicatedly been searching for evidence of the Lone Woman's life. He scoured its beaches and sandstone cliffs, drilling exploratory holes, and consulting ancient maps in hopes of uncovering artifacts. Finally in 2012, he found a cave that measures 75 feet long and 10 feet high, and demanded 40,000 buckets-worth of sand to unearth. He's "90 percent sure" this is where Juana Maria would have spent much of her time.

12. FURTHER DISCOVERIES ON THE REAL ISLAND OF THE BLUE DOLPHINS HAVE SPARKED CONTROVERSY.

Another team found redwood boxes containing 200 stone blades, harpoon points, and bone fishhooks. But when the Navy announced plans to relocate these artifacts from San Nicolas to the Naval Air Weapons Station in China Lake, California, archaeologists and Native American leaders banded together, creating a petition to stop them. The main concern is the move could damage these precious artifacts between the risks of travel and a drier climate that could make them brittle. But the Navy's response was essentially that the objects would receive the highest care and consideration.

13. IN BOTH REAL LIFE AND FICTION, THE LONE WOMAN DIES SHORTLY AFTER DISCOVERY.

In Zia, Karana peacefully passes away shortly after her niece finds her. In real life, Maria was welcomed into the Santa Barbara mission, where she entertained residents, singing and dancing. But just seven weeks into her stay, Maria passed away. She was buried at the mission's cemetery, within the Nidever family's plot. In 1928, the Daughters of the American Revolution remembered her with a commemorative plate placed on her grave.

14. SCOTT O'DELL ASSURED HIS LEGACY WITH A SPECIAL AWARD.

In 1982—seven years before his passing—the author created his own literary honor: the Scott O'Dell Award for Historical Fiction. Awarded to children's and young adult books with a focus on history, the award was O'Dell's way of encouraging other writers to create Island of the Blue Dolphin books of their own. His hope was that such engaging explorations would engage American children in history. Winners have included Jennifer L. Holm's Depression era-set Full of Beans, Jack Gantos' autobiographical Dead End in Norvelt, and Rita Williams-Garcia's 1968 Oakland-set One Crazy Summer.

15. ISLAND OF THE BLUE DOLPHINS HAS MAINTAINED POPULARITY FOR OVER 57 YEARS.

The year of its release, O'Dell's novel was celebrated with the Newbery Medal, awarded to "the most distinguished contribution to American literature for children." Since then, Island of the Blue Dolphins has ended up on countless reading lists for school assignments. Even as the conversation evolves around what it means to have a white man reconstruct—or flat-out re-imagine—the life and culture of a lost Native American tribe, the book holds a hallowed place in children's historical fiction and in the hearts of many writers and readers. Plus Island of the Blue Dolphins boasts more than 6.5 million copies in print, and is roundly counted as one of the most popular novels of the 20th century.