September 5 is the anniversary of the assassination of one of the greatest warriors the world has ever known: Tasunke Witko — better known as Crazy Horse.

On that day in 1877, at Fort Robinson, Nebraska, he was bayoneted in the back while being restrained and placed under arrest. He had come in peace, but was killed nonetheless.

Crazy Horse was a renowned war leader who played a leading role in pretty much every major military excursion the Lakota engaged in during his lifetime, each one more historic than the last. Under his command, the Lakota repeatedly defeated) the U.S. Army on American soil.

He was a defender of the Lakota People and their allies and a protector of the land when it was being invaded by settlers, gold miners, and the U.S. Cavalry. It was he who led the Lakota to resounding victories at the Fetterman Fight, the Battle of the Rosebud, and Greasy Grass (aka, Little Big Horn).

While he never signed a treaty, his leadership, skill, and strategic brilliance during Red Cloud War paved the way for the Fort Laramie Treaty of 1868, which firmly established Lakota territory and sealed their claim to the Black Hills, which stands to this day.

He was adored and revered by his people and respected by his enemies, but some of the other chiefs were jealous of him. They stoked the fears that the U.S. government and its agents already had about Crazy Horse. They were afraid of his influence and believed that if anyone could lead an insurrection, it was him. That’s why they say the Army planned to imprison him and why he was, quite literally, stabbed in the back.

Crazy Horse was Oglala and Miniconjou Lakota, two subdivisions of the Oceti Sakowin (Great Sioux Nation). According to the Lakota, he was born near Bear Butte, a sacred site in the Black Hills of South Dakota.

He was a nonconformist, who tribal elders described in oral history to tribal members as quiet and even reclusive. While he was highly spiritual and participated in ceremonies, elders say he didn’t consider himself bound to protocol. Instead, he preferred to follow his own dreams and visions.

It’s been said that a vision gave his life purpose. During a Hanbleceya (or “vision quest”), a Lakota ceremonial rite where one isolates oneself up on a hill and goes without food and water for days, Crazy Horse saw a man riding on horseback during a thunderstorm. Legend has it that the man wore his hair loose with a single feather tied to it and had a lightning bolt painted on his face with hailstones dotting his body. People reached out to grasp the rider, but could not hold him. Crazy Horse realized that he would become that fierce man and that he would fight for his people. He was directed to toss dust over his horse and place a stone behind his ear before battle and told that as long as he took nothing for himself, no bullet or arrow could kill him.

Crazy Horse was rewarded for his valor. The highest honor was bestowed upon him — that of “shirt wearer.” Becoming a shirt wearer is one of the highest formal honors in Lakota Native American Indian culture. Upon accepting the shirt, the men who wore them became an example for others. The were to serve the people and live according to Lakota values. Such a distinction set Crazy Horse apart as a head warrior who carried the power of the Lakota Nation.