We shall overcome
... Part of the melody seems to be related to two European songs from the 1700s, Prayer of the Sicilian Mariners and O Sanctissima. Enslaved Black people in the U.S. mixed and matched similar tunes in the songs Ill Be All Right and No More Auction Block For Me.
After 1900, it seems the lyrics of another gospel song, Ill Overcome Someday by the Methodist minister and composer Reverend Dr. Charles Tindley, were added to the musical mixthough the music was very different. Around 1945, gospel arrangers Atron Twigg and Kenneth Morris apparently put together the essential pieces of the now-famous words and melody.
Well Overcome first appeared as a protest song during a 19451946 labor strike against American Tobacco in Charleston, South Carolina. African American women strikers seeking a pay raise to 30 cents an hour sang as they picketed. I Will Overcome was a favorite song of Lucille Simmons, one of the strikers. But she gave the song a powerful sense of solidarity by changing the I into We as they sang together. Other lyrics were improvised for pro-union purposes, including We will organize, We will win our rights, and We will win this fight.
In 1947, Simmons brought the song to Highlander Folk School and shared it with other labor activists there. Zilphia Horton, head of the schools cultural program, learned it and later taught it to Pete Seeger. At some point, the nationally known folk singer revised the lyrics We will to We shall ...
https://www.kennedy-center.org/education/resources-for-educators/classroom-resources/media-and-interactives/media/music/story-behind-the-song/the-story-behind-the-song/we-shall-overcome/