They say behind every great man stands a great woman. Coretta Scott King, civil rights activist and widow of Rev. Dr. Martin Luther King Jr., was no exception.

In partnership with her husband throughout the 1950s and 1960s, Mrs. King played an important role in the civil rights movement. In 1955 she took part in the Montgomery Bus Boycott and most prominently, perhaps, she worked hard to pass the Civil Rights Act of 1964.

“I am convinced that if I had not had a wife with the fortitude, strength and calmness of Coretta, I could not have stood up amid the ordeals and tensions surrounding the Montgomery movement,” Dr. King said of his wife.

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Contrary to over-simplistic accounts of the late Mrs. King as simply Dr. King’s widow, she was a formidable political activist in her own right, who played a major role in the civil rights struggle.

“She was very much an activist even before she met Dr. King and even attended the Progressive Party convention in 1948,” says Steve Klein, communications director at the Martin Luther King Jr. Center for Nonviolent Social Change in Atlanta.

During the struggle, King was actively involved, often behind the scenes, in the planning of marches and boycotts and gave speeches all over the country, sometimes standing in for her husband.

“She was a fundraiser for the movement,” says Klein. “She used her creative talents and singing ability to stage Freedom Concerts across the country, which raised some pretty good cash.”

Following Martin Luther King’s assassination in 1968, King threw herself into celebrating her husband’s life and keeping his legacy alive. In the process she transformed into a worldwide human rights leader.

Her progressive leadership broadened to include women’s rights, LGBT rights, economic issues, world peace, and various other causes. “I’m more determined than ever that my husband’s dream will become a reality,” the young widow said soon after his slaying.

King, despite raising four young children alone, was the driving force behind Atlanta’s King Center and served as president until she passed the reins to her son Dexter Scott King. During her tenure she dedicated herself to providing national and international programs that have trained tens of thousands of people in Dr. King’s nonviolence philosophy.

She was a savvy lobbyist that spearheaded the fifteen-year campaign to get her husband’s birthday recognized as a national holiday, achieving success in 1986. “If it wasn’t for her, Martin’s legacy would not have lived as long as it has,” says Atlanta journalist and university lecturer Sidmel Estes.

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King was a woman with her own mind and amidst fierce opposition from the some factions of the black church she spoke out about the struggles of gays and lesbians. “She felt this was a valid human rights struggle,” says Klein, who worked with King from 1971 until her death in 2006. “She was a voice for tolerance while decrying bigotry.”

“Coretta Scott King was a champion of gay rights and saw it beyond being merely a civil rights issue. She had the up close and personal experience of having an openly gay person as her special assistant for 23 years — Lynn Cothren — who was also a prominent LBGT activist,” says Sharon J. Lettman-Hicks, executive director of the Washington-based National Black Justice Coalition.

In 1986, she traveled to South Africa and met with Winnie Mandela, while Mandela’s husband Nelson Mandela was still a political prisoner. In 1987, she helped lead the Mobilization Against Fear and Intimidation in Forsyth County Georgia.

Though, her life has not passed without controversy. The King Center has, over the years, been embroiled in controversy as the siblings battled with each other about the handling of their parent’s legacy.

Nevertheless, relations seemed to have thawed and just this month Rev. Bernice King, the youngest daughter of Dr. King, was named the CEO of the King Center. Her brother Dexter Scott King, who she had previously taken to court, continues to serve as chairman.

King’s funeral in 2006 at New Birth Missionary Baptist Church in Georgia had the pomp and circumstance befitting an elder-statesman, with then-U.S. President George W. Bush attending, as well as three former presidents and their wives, prominent political and civil rights leaders, including then-U.S. senator Barack Obama.

“The funeral lasted so long because so many people wanted to share their experiences of working with her,” says Estes, former executive producer at WAGA FOX 5 Atlanta, who spearheaded the station’s news coverage of the eight-hour proceedings.

“She was the invisible backbone of the civil rights movement because without her Martin would not have been able to do all the things he was able to do,” says Estes. “Not only did she keep the family together she looked out for him.”

In many ways Coretta Scott King led a life of extraordinary strength and courage. Some would even say without this formidable woman by his side, Dr. King’s legacy may never have risen to such heroic proportions.

Follow Kunbi Tinuoye on Twitter at @Kunbiti