“We Shall Overcome” became particularly popular in the 1960s, during the Civil Rights movement in America, after Pete Seeger picked it up, adapted it, and taught it to his audiences to sing. However, the song had a half century (or so) to evovle and expand its meaning before Seeger and Joan Baez popularized it during the folk revival.The melody dates back to before the Civil War, from a song called “No More Auction Block For Me.” Originally, the lyrics were “I’ll overcome someday,” which dates back to a turn-of-the-20th-century song by the Reverend Charles Tindley of Philadelphia.

The song didn’t appear on a large scale until 1946, during a labor strike at the American Tobacco Company. One of the women striking that day – Lucille Simmons – began singing slowly, “Deep in my heart I do believe we’ll overcome some day.”
Zilphia Horton, whose husband was the co-founder of the Highlander Folk School (aka Highlander Research and Education Center), learned the song from Simmons and, a year later, taught it to folk singer Pete Seeger.
The adaptation of the song to its current lyric is often attributed to Pete Seeger, but there is some debate over whether Seeger changed the lyric to “We Shall Overcome,” or whether this was the doing of others at the Highlander School. At any rate, Seeger taught the song to other folksingers and, a decade later (1959), the song was brought back to the Highlander School.
Since then, “We Shall Overcome” has spread from folksinger to folksinger, through protests and peace rallies, song circles, and open mics. It was recorded by Joan Baez in 1963 and became a major anthem of the Civil Rights movement.