A native of Kansas City, Missouri, Rev. John A. Alexander served as a pastor in his home state in the late 1910s and 1920s. He came to Des Moines, Iowa to be pastor at St. Paul AME Church in 1932 and was the officiant for the funeral service for prominent lawyer George Woodson in 1933. Rev. Alexander engaged in civic activities and preached at other churches including in Dallas Center in 1934. He gave a talk at First Evangelical Church in Des Moines in 1935. He left St. Paul AME in 1936 to be a pastor of Ebenezer AME Church in Evanston, Illinois.

Rev. Alexander then held positions in Indianapolis, Indiana, Detroit, Michigan, and Chicago, Illinois, all three churches with the name Bethel AME. He was in Indiana from about 1941 to 1949, then Michigan, and back to Illinois from 1952 to 1958. He finished his career in Philadelphia, Pennsylvania at Mt. Pisgah AME and left the pulpit around 1964. Rev. Alexander died in Philadelphia on April 28, 1970. His death certificate lists his burial place as Mount Lawn Cemetery in Sharon Hill, Pennsylvania.