John, also known as Eugene, was born into slavery but obtained his freedom in 1837. It is said that he was involved in the great gold rush of 1849. He was a barber. He settled in Buffalo, New York with his wife Prudence. Simpson was one of the founders of East Presbyterian Church in 1850. When that church dissolved, he co-founded St. Philip's Episcopal Churh and was one of it leaders until is death.
His daughter, Frances became one of the first Black school teachers in Buffalo at the segregated Vine Street African School.
