FARGO - Crazy Horse is remembered as an uncompromising Lakota warrior who never signed a treaty and who played a leading role in the stunning defeat of Lt. Col. George Custer at the Battle of the Little Bighorn.

He refused to be photographed, but his likeness is being carved on a mammoth scale in a mountain in the Black Hills, and he remains an enigma in spite of his lasting fame.

It turns out the sculptor, Korczak Ziolkowski, used models to help ensure authenticity - three Lakota men who were descendants of Crazy Horse and a fourth descendant who allowed his photograph to be used in a composite sketch that became a template for the stone monument, which will stand 563 feet tall.

The story of the undisclosed models was kept secret by Crazy Horse's descendants, members of the Clown family, who for generations kept quiet about their connection, originally fearing retribution.

But now the Clown family of the Cheyenne River Indian Reservation in South Dakota has come forward with the oral history of Crazy Horse, as passed down within the family and never told publicly until the publication of their book, "Crazy Horse: The Lakota Warrior's Life & Legacy."

Following publication of the book, in 2016, members of the Clown family and the man entrusted to put their story in writing, William Matson, have toured the country to talk about the genuine Crazy Horse, not the mythical character in countless books and films as depicted by others.

Their quest to spread the family's view of Crazy Horse - Tashunke Witko, or His-Horse-Is-Crazy, in Lakota - will take members of the Clown family and Matson to Fargo for an appearance and book signing on Sunday, May 13.

"Now is the time to correct all assumptions or untruths," said Floyd Clown, one of Crazy Horse's grand nephews. "So that's what we're doing."

Crazy Horse's family essentially went into hiding soon after the warrior was killed while surrendering at Fort Robinson in Nebraska in 1877.

It was more than a year after the Battle of the Little Bighorn, and the U.S. Army had intensified its military campaign against Lakota and Cheyenne bands considered hostile because they refused to relocate to reservations. Instead, they wanted to continue roaming and hunting buffalo, which were becoming increasingly scarce.

After being doggedly pursued by soldiers, Crazy Horse agreed to surrender because he was assured that his people would be allowed to hunt in the Black Hills, which the Lakota consider sacred, according to the Clown family.

But once in military custody, Crazy Horse believed he had been mislead and tried to escape. In the struggle, a soldier bayoneted Crazy Horse, delivering a mortal wound. He died on Sept. 5, 1877.

Crazy Horse's father, who like his son had been staying with the Oglala Lakota, was uncomfortable remaining with that tribe. Some of its members had turned against Crazy Horse, so he took his family to the Sicangu Lakota and later the Minnikojou Lakota, who now reside at Cheyenne River.

In fact, according to the Clown family, a common misnomer is that Crazy Horse was Oglala. He actually was entirely Minnikojou, from both sides of his family, a misconception they address in the book.

Even among their fellow Minnikojous, the Crazy Horse family and their descendants lived quietly, not calling attention to their connection to the famous warrior, who was viewed by the government as a renegade, and his relatives as potential troublemakers.

Their actions were scrutinized by government agents and subjected to a probate court proceeding begun in 1920, for reasons they didn't understand, involving a family member's 1905 death - resulting in records that, decades later, would help establish the Clown family's direct connection to Crazy Horse.

Family members suspected the reason for the probate inquiry was to establish their connection to Crazy Horse, and it only reinforced their conviction that they should keep the link secret. As a boy, Floyd Clown was told not to discuss Crazy Horse. Around the same time, a family member was shot to death, heightening fears they were being hunted.

The decades of submerging their connection started to come to an end in 1998, when the family had a vision quest, which convinced them to "Stand up and tell your story."

Bill Matson, meanwhile, was on a quest of his own. His father, who was writing a book about the Battle of the Little Bighorn from the Indian perspective, was on his deathbed when he asked his son to carry on the project.

Matson reluctantly agreed and, through roundabout means, was put in touch with the Clown family, who became convinced of his sincerity after a sweat lodge ceremony. The result of their collaboration was a four-part documentary film, followed years later by the book.

One of the most common myths about Crazy Horse is that he wore a stone talisman dangling from his ear, an error from one of Crazy Horse's early biographers that was frequently repeated. Actually, it was Crazy Horse's horse who wore a stone as protection against bullets and arrows, the Clowns say.

For Matson, one of the most interesting revelations was Crazy Horse's role in the Battle of the Little Bighorn. During a point in the battle when the outcome was in question, he charged through a line of dismounted soldiers. Unscathed, he decided to turn around and charge again - a bold move that spurred on the other warriors.

Years later, when bitterness after the battle faded, a Lakota named Henry Standing Bear recruited Ziolkowski, a well-known sculptor who once had worked on Mount Rushmore, to carve a mountain sculpture of Crazy Horse. A relative of Standing Bear's asked members of the Clown family - Floyd Clown's uncles - to travel to the Black Hills to serve as models.

The Clowns had one condition: Ziolkowski couldn't reveal the source of the model. "He kept his promise to our family," Floyd Clown said. The Clown family revealed the story to Ruth Ziolkowski, Korczak's widow in 2004, he said. She has since died.

Ironically, the Clown family's documented connection to Crazy Horse was legally recognized when descendants went to court to block the sale of Crazy Horse malt liquor, which they considered sacrilegious.

The family prevailed in 2001, and under a settlement with the brewer got a public apology and symbolic gifts: 32 blankets, 32 braids of sweetgrass, 32 twists of tobacco and seven horses.

Floyd Clown said he hopes his family's efforts will inspire other Native American families to follow suit. "We're showing how all native families should protect their grandfather's name," he said. "By example, this is how it's done."