Cromwell was born April 22, 1878, on a farm at 39th and Harrison in Kansas City, Missouri, to Eliza (née Hilton) and Benjamin H.

[2] He was elected mayor of Kansas City in 1922 and served one two-year term.

In 1936, he was made president of the park board, succeeding Judge Joseph A. Guthrie.

In 1938, Cromwell was appointed supervisor of creation for the park department.

[2] In the 1950s, Cromwell was a deputy sheriff, working as bailiff in division 4 of the Jackson County Circuit Court under Judges Thomas R. Hunt and Duvaul P.

Later in life, Cromwell lived at the Westport Arms apartments in Kansas City.

[2] Cromwell died on April 14, 1955, at the Trinity Lutheran Hospital in Kansas City.