Stokely Carmichael was a U.S. civil-rights activist who in the 1960s originated the Black nationalism rallying slogan, “Black power.” Born in Trinidad, he immigrated to New York City in 1952. While attending Howard University, he joined the Student Nonviolent Coordinating Committee and was jailed for his work with Freedom Riders. He moved away from MLK Jr’s nonviolence approach to self-defense.

In 1954, at the age of 13, Stokely Carmichael became a naturalized American citizen and his family moved to a predominantly Italian and Jewish neighborhood in the Bronx called Morris Park. Soon Carmichael became the only Black member of a street gang called the Morris Park Dukes. In 1956, he passed the admissions test to get into the prestigious Bronx High School of Science, where he was introduced to an entirely different social set—the children of New York City’s rich white liberal elite. Carmichael was popular among his new classmates; he attended parties frequently and dated white girls.

Even at that age, he was highly conscious of the racial differences that divided him from his classmates. Carmichael later recalled his high school friendships in harsh terms: “Now that I realize how phony they all were, how I hate myself for it. Being liberal was an intellectual game with these cats. They were still white, and I was Black.”

Although he had been aware of the American civil rights movement for years, it was not until one night toward the end of high school, when he saw footage of a sit-in on television, that Carmichael felt compelled to join the struggle. “When I first heard about the Negroes sitting in at lunch counters down South,” he later recalled, “I thought they were just a bunch of publicity hounds. But one night when I saw those young kids on TV, getting back up on the lunch counter stools after being knocked off them, sugar in their eyes, ketchup in their hair—well, something happened to me. Suddenly I was burning.” He joined the Congress of Racial Equality (CORE), picketed a Woolworth’s store in New York and traveled to sit-ins in Virginia and South Carolina.

A stellar student, Carmichael received scholarship offers to a variety of prestigious predominantly white universities after graduating high school in 1960. He chose instead to attend the historically Black Howard University in Washington, D.C. There he majored in philosophy, studying the works of Camus, Sartre and Santayana and considering ways to apply their theoretical frameworks to the issues facing the civil rights movement. At the same time, Carmichael continued to increase his participation in the movement itself.

While still a freshman in 1961, Carmichael went on his first Freedom Ride—an integrated bus tour through the South to challenge the segregation of interstate travel. During that trip, he was arrested in Jackson, Mississippi for entering the “whites only” bus stop waiting room and jailed for 49 days. Undeterred, Carmichael remained actively involved in the civil rights movement throughout his college years, participating in another Freedom Ride in Maryland, a demonstration in Georgia and a hospital workers’ strike in New York. He graduated from Howard University with honors in 1964.

Carmichael left school at a critical moment in the history of the civil rights movement. The Student Nonviolent Coordinating Committee (SNCC) dubbed the summer of 1964 “Freedom Summer,” rolling out an aggressive campaign to register Black voters in the Deep South. Carmichael joined SNCC as a newly minted college graduate, using his eloquence and natural leadership skills to quickly be appointed field organizer for Lowndes County, Alabama. When Carmichael arrived in Lowndes County in 1965, African Americans made up the majority of the population but remained entirely unrepresented in government. In one year, Carmichael managed to raise the number of registered Black voters from 70 to 2,600, 300 more than the number of registered white voters in the county.

Unsatisfied with the response of either of the major political parties to his registration efforts, Carmichael founded his own party, the Lowndes County Freedom Organization. To satisfy a requirement that all political parties have an official logo, he chose a Black panther, which later provided the inspiration for the Black Panthers (a different Black activist organization founded in Oakland, California).

At this stage in his life, Carmichael adhered to the philosophy of nonviolent resistance espoused by Dr. Martin Luther King, Jr. In addition to moral opposition to violence, proponents of nonviolent resistance believed that the strategy would win public support for civil rights by drawing a sharp contrast—captured on nightly television—between the peacefulness of the protestors and the brutality of the police and hecklers opposing them. However, as time went on, Carmichael—like many young activists—became frustrated with the slow pace of progress and with having to endure repeated acts of violence and humiliation at the hands of white police officers without recourse.

By the time he was elected national chairman of SNCC in May 1966, Carmichael had largely lost faith in the theory of nonviolent resistance that he—and SNCC—had once held dear. As chairman, he turned SNCC in a sharply radical direction, making it clear that white members, once actively recruited, were no longer welcome. The defining moment of Carmichael’s tenure as chairman—and perhaps of his life—came only weeks after he took over leadership of the organization.

In June 1966, James Meredith, a civil rights activist who had been the first Black student to attend the University of Mississippi, embarked on a solitary “Walk Against Fear” from Memphis, Tennessee to Jackson, Mississippi. About 20 miles into Mississippi, Meredith was shot and wounded too severely to continue. Carmichael decided that SNCC volunteers should carry on the march in his place, and upon reaching Greenwood, Mississippi on June 16, an enraged Carmichael gave the address for which he would forever be best remembered. “We been saying ‘freedom’ for six years,” he said. “What we are going to start saying now is ‘Black Power.'”

The phrase “Black power” quickly caught on as the rallying cry of a younger, more radical generation of civil rights activists. The term also resonated internationally, becoming a slogan of resistance to European imperialism in Africa. In his 1968 book, Black Power: The Politics of Liberation, Carmichael explained the meaning of Black power: ”It is a call for Black people in this country to unite, to recognize their heritage, to build a sense of community. It is a call for Black people to define their own goals, to lead their own organizations.”

Black power also represented Carmichael’s break with King’s doctrine of nonviolence and its end goal of racial integration. Instead, he associated the term with the doctrine of Black separatism, articulated most prominently by Malcolm X. “When you talk of Black power, you talk of building a movement that will smash everything Western civilization has created,” Carmichael said in one speech. Unsurprisingly, the turn to Black power proved controversial, evoking fear in many white Americans, even those previously sympathetic to the civil rights movement, and exacerbating fissures within the movement itself between older proponents of nonviolence and younger advocates of separatism. Martin Luther King called Black power “an unfortunate choice of words.”

In 1967, Carmichael took a transformative journey, traveling outside the United States to visit with revolutionary leaders in Cuba, North Vietnam, China and Guinea. Upon his return to the United States, he left SNCC and became Prime Minister of the more radical Black Panthers. He spent the next two years speaking around the country and writing essays on Black nationalism, Black separatism and, increasingly, pan-Africanism, which ultimately became Carmichael’s life cause.

In 1969, Carmichael quit the Black Panthers and left the United States to take up permanent residence in Conakry, Guinea, where he dedicated his life to the cause of pan-African unity. “America does not belong to the Blacks,” he said, explaining his departure from the country. Carmichael changed his name to Kwame Toure to honor both the President of Ghana, Kwame Nkrumah, and the President of Guinea, Sekou Toure.

In 1968, Carmichael married Miriam Makeba, a South African singer. After they divorced, he later married a Guinean doctor named Marlyatou Barry. Although he made frequent trips back to the United States to advocate pan-Africanism as the only true path to liberation for Black people worldwide, Carmichael maintained permanent residence in Guinea for the rest of his life. Carmichael was diagnosed with prostate cancer in 1985, and although it is unclear precisely what he meant, he said publicly that his cancer “was given to me by forces of American imperialism and others who conspired with them.” He died on November 15, 1998, at the age of 57.

An inspired orator, persuasive essayist, effective organizer and expansive thinker, Carmichael stands out as one of the preeminent figures of the American civil rights movement. His tireless spirit and radical outlook are perhaps best captured by the greeting with which he answered his telephone until his dying day: “Ready for the revolution!”