[This is dedicated to Mark Marqusee, who taught me the history below, and Jasiri X, who inspired me to write it.]

Muhammad Ali and Dr. Martin Luther King Jr. have been dominating my thoughts recently, and not only because their birthdays just passed, a mere two days apart. Ali was admitted to the hospital on Thursday for being in a “non-responsive state”. This was happening as news that Selma, the film about Dr. King’s 1965 civil rights campaign was being both snubbed at the Oscars and hammmered by President Lyndon Johnson’s old apparatchiks, aghast that the film did not give LBJ what they believed was his proper due as a civil-rights hero. The national fear that these could have been Ali’s last days, as well as the concern that LBJ wasn’t getting enough of Dr. King’s reflected glory, could cause your brain to short-circuit if you were familiar with the actuality of their history, not to mention their private friendship during the 1960s.

On the face of it, Muhammad Ali and Martin Luther King would have had no reason for either friendship or common cause. Ali was a member of the Nation of Islam, an organization staunchly opposed to King’s integrationist worldview. The NOI was withering in its assessment of King, most famously with Malcolm X’s contention that King in 1963 had led not a March but a “Farce on Washington.” King, in response wrote that he believed the Nation of Islam was “made up of people who have lost faith in America, who have absolutely repudiated Christianity, and who have concluded that the white man is an incorrigible devil.” He said we needed a movement based in love and not “the hatred and despair of the black nationalist.” As for Muhammad Ali, he mocked King’s integrationist ideal in 1964 saying, “I’m not going to get killed trying to force myself on people who don’t want me. Integration is wrong. White people don’t want it, the Muslims don’t want it. So what’s wrong with the Muslims? I’ve never been in jail. I’ve never been in court. I don’t join integration marches and I never hold a sign.” King’s ally Roy Wilkins responded by saying that “Cassius Clay [Ali’s name at birth] may as well be an honorary member of the white citizen councils.”

And yet, as the 1960s moved forward, Muhammad Ali and Dr. Martin Luther King formed a common bond forged through the common hatred showered upon them and their loved ones. As John Carlos, famed 1968 Olympian and protester, once said to me, “If there was an Olympic sport for number of death threats received back then, King and Ali would be fighting for the gold.” I have seen some of these death threats, and they are terrifying in a way that Twitter threats, awful as they are, simply are not. They are written often with a rational hand and comprise thousands of words, with knowledge of their targets’ movements, and solemn promises of when their lives or the lives of their children would end.

As the 1960s propelled forward, both men were part of a common black freedom struggle that was blurring the lines between “nationalism” vs. “integrationism” taking on not only the legal barriers to integration set forth by Jim Crow but the intractable racism of the North. We know of their friendship only because of those invaluable stenographers at the FBI. Here is one FBI wiretap summary with Martin Luther King Jr. in which Muhammad Ali is referred to derisively as “C”, for Cassius Clay.

“MLK spoke to C, they exchanged greetings. C invited MLK to be his guest at the next championship fight. MLK said he would like to attend. C said he is keeping up with MLK and MLK is his brother and he’s with him 100 percent but can’t take any chances, and that MLK should take care of himself and should ‘watch out for them whities.’”

(Interestingly, we know of these wiretaps only because of the March 8, 1971 break-in of activists into an FBI office. They chose March 8 because it was the night of first Frazier-Ali and they knew the guards would be distracted with the rest of the country.)

Ali and Dr. King saw their connection become unbreakable in 1967 when King made the courageous decision, against the wishes of his advisers, to take a stand against President Johnson’s escalation of the war in Vietnam. By this time, Ali had already become the most visible draft resister in the country, standing strong despite the stripping of his heavyweight title and the threat of a five-year prison sentence in Leavenworth.

The press was hounding King about why he wasn’t just focusing on the “domestic issue” of civil rights, and King took that moment to draw upon thoughts of his private friend and said, “Like Muhammad Ali puts it, we are all—black and brown and poor—victims of the same system of oppression.”

The two men also appeared together at a fair-housing rally in Ali’s hometown of Louisville, Kentucky. There, Ali said, “In your struggle for freedom, justice and equality, I am with you. I came to Louisville because I could not remain silent while my own people, many I grew up with, many I went too school with, many my blood relatives, were being beaten, stomped and kicked in the streets simply because they want freedom, and justice and equality in housing.” Ali was now a protester. Dr. King was now an internationalist. The boxer and the preacher had come together as one.

It took a bullet on April 4, 1968, to end this fellowship between Muhammad Ali and Martin Luther King Jr. For both men, it required losing the power of speech, whether in death or as a result of Parkinson’s disease, to be embraced by the country as a whole. At a time when a new movement is finding its feet to stand against police violence and stand for the deceptively simple request for people to see that #BlackLivesMatter, we would do well to remember the hatred endured by both these men in the name of delivering truth. At a time when this movement is attempting to forge connections with oppressed people across the globe, from Ferguson to Gaza, and trying to figure out how to deal with a frustrating president in the Oval Office as well as a class of civil-rights leaders reluctant to give up the microphone, it is worth remembering how much hate King and Ali proudly invited upon themselves. Their only moral compass was one that pointed toward standing with the powerless against the powerful. That was the basis of their friendship. That should be basis of our own solidarity as we move forward today.