When Martin Luther King Jr. spoke, with his famously sonorous vibrato, he was tapping into a Black musical tradition that animated the Civil Rights Movement, according to Ambre Dromgoole, assistant professor of Africana studies and music in the College of Arts and Sciences.

“The rhythm and tone of his speech, the repetition, the call-and-response, the pacing, is absolutely connected to not only Black preaching and sermonic traditions, but also to Black musical traditions, Black folk traditions, that people would have recognized as they listened to them,” said Dromgoole, an expert in Black sacred music, gender and performance. “There’s a world in his voice, in his speech, his tonality, that people tap into when they hear him.”

That Black musical tradition included the folk spirituals that morphed into freedom songs, such as “Wade in the Water” and “We Shall Not Be Moved.” Civil rights leaders leveraged those songs to inspire the solidarity and sense of purpose that made demonstrations possible.

Protestors sang freedom songs at mass meetings before marches. They sang while they were getting arrested and they sang through the bars of prisons when they were jailed.

“They are meeting. They’re galvanizing. It matters that they have song and sound and a collective ethos to push them forward,” she said.

Freedom songs often began as folk spirituals created and sung by enslaved people hundreds of years ago. By the 1950s and ’60s, the spirituals had sunk into the culture’s bones. Just as MLK did with his speeches, civil rights leaders used that cultural tradition to encourage people to join the Civil Rights Movement, Dromgoole said.

“The melodies and the rhythms of the freedom songs are familiar,” she said, “and that resonates with people. That allows them to feel more connected to each other, more ready to engage in acts that might be considered dangerous, more willing to move past their fear and stick with it.”

The songs’ simple messaging was highly adaptable to the current political moment.

In “Wade in the Water,” the lyric “God’s going to trouble the water” originally meant that by agitating a body of water God would create a cover for people escaping their enslavers. Civil rights leaders understood the lyric to mean God would make conditions ripe for organizing and freedom, whether political or spiritual, Dromgoole said. “They really used that idea of wading in the water to mean, in spite of any nerves or trepidation you might feel, you must always be willing to wade into trouble in order to make change.”

In “We Shall Not Be Moved,” the lyric “like a tree planted by the waters/we shall not be moved” refers to Bible verses describing a steady faith in God. In the 1960s, activists changed the words to denounce then-governor of Mississippi, Paul B. Johnson Jr.: “Governor Johnson, he shall be removed/just like a pail of garbage in the alley/he shall be removed.”

“If I wanted to sing it today, I might say ‘Minneapolis, they will not be moved,’” Dromgoole said. “The ability to take those lyrics and transform them to fit a certain moment, and have that messaging come through very clearly, is why freedom songs become an effective tool.”

The songs also offered women a vehicle to assume greater power within the Civil Rights Movement. They not only led the singing at mass meetings, but also discussions about the movement’s strategies and next steps. The meetings were often held in churches, where men typically dominated.

“But in this mass meeting space, somebody like Fannie Lou Hamer, an organizer, a song leader, an orator – and there were many like her – is given the clearance to be in a pulpit as recognition of her leadership capacity,” Dromgoole said.

Female singers and musicians such as Nina Simone, Roberta Flack and Alice Coltrane carried on that tradition after Congress passed the Civil Rights Voting Act in 1965.

“They’re mixing different genres, allowing people to think about what liberation – not only physically and legally, but also spiritually and atmospherically – might look like for Black people,” Dromgoole said.

The Black musical tradition that inspired King and his followers gave people a vision of a future in which freedom and liberation were possible.

It is still an effective tool for protest today, Dromgoole said.

“It’s all part of the same pipeline, of tapping into historical worlds in order to imagine and create new ones,” she said. “Sound is a portal to past, present and future orientations toward struggle and freedom.”