William Jackson was born in 1818 in Virginia to free black parents. He was ordained September 16, 1841 at the Monumental Baptist Church in Philadelphia, having moved to Philadelphia in 1831. He was an agent on the Underground Railroad. He was incarcerated in the local jail after assisting a church member who was a fugitive slave. In 1854, because of the uproar over his imprisonment and release, William Jackson moved to New Bedford MA leaving his family behind in Philadelphia. He became the pastor of the Second Baptist Church serving as their pastor from 1855-1859. He also befriended Frederick Douglas, who was living in New Bedford at the time. In 1859, a splinter group from Second Baptist, led by William Jackson formed the Salem Baptist Church of New Bedford. He served as pastor there from 1859 to 1870. These two churches merged in 1895 formed the Union Baptist Church of New Bedford which still exists today.
He also became a founding member of the New Bedford Vigilance Aid Society, a group that assisted fugitive slaves in the effort to reach freedom. He opposed efforts which promoted the return of black people to west Africa through the American Colonization Society.
Rev. Jackson entered the Army (July 14, 1863) and became chaplain of the 54th and 55th Massachusetts Colored Infantries and was the first “colored man” to receive a commission from the army. In 1864 he resigned his commission and returned to his ministry in New Bedford.
He was pastor of Congdon Street Baptist Church, Providence, RI from 1870 to 1878 and later, Bethany Baptist Church, Newark, NJ. Rev. Jackson was influential in the formation of the American Baptist Missionary Convention, incorporated in 1848, and the New England Missionary Baptist Convention incorporated in 1874, both organizations reaching beyond state lines and dedicated to “racial uplift.” This outstanding minister of the Gospel and soldier of freedom died in 1900 at the age of 82 and was buried in Oak Grove Cemetery, New Bedford.