Born: July 20, 1885, Boston, Massachusetts.
Died: August 21, 1972, Northampton, Massachusetts.
Buried: Abels Hill Cemetery (also known as Chilmark Cemetery), Martha’s Vineyard, Massachusetts.
Harlow was the son of Samuel Allen Harlow and Caroline Mudge Usher.
He attended Harvard University, Union Theological Seminary, Columbia University, and Hartford Theological Seminary.
Ordained a Congregational minister in 1912, he was a chaplain and sociology teacher at the International College in Smyrna, Turkey (1912–22).
When World War I broke out, he served as YMCA director for the American forces in France.
In 1923, he joined Smith College, Northampton, Massachusetts, serving over 30 years as a professor of religion and social ethics.
He traveled overseas as a lecturer for the Carnegie Endowment for International Peace, and was a visiting professor at Pierce College in Athens, Greece (1945–46).