African American spirituals originated through an amalgamation of African religion and music with the Christian religion of slave owners and Christian hymns. Slaves were not allowed to worship by themselves; therefore, they used the traditions of their culture, blending them with the hymns taught them in the white churches.
Spirituals were sung in a call and response manner or as a "shout," which resembled traditional African dancing. According to negrospirituals.com, shouts were held after regular religious services. They were an ecstatic experience with the music and dancing building to a fervor where, "Women screamed and fell. Men, exhausted, dropped out of the ring."
African American spirituals as we know them today began in the early 1800's. Slaves who had been brought to Christian churches learned how God had set the captives free. They incorporated this hope for freedom in the songs they sang by using the words heard in the churches.
During the time of slavery as well as after, the songs held messages that covertly related information to the African American community. Words and phrases carried specific meaning, such as "home," which meant a place of freedom or "The Gospel Train," which was understood to mean the Underground Railroad.
Later, during the early 1900s, spirituals began to be used as hymns of praise. They soon began to relate to the troubles experienced by African Americans during their struggle for Civil Rights.