Born: November 29, 1879, Philadelphia, Pennsylvania.
Died: April 3, 1964, New York City.
Buried: Community Church of New York Unitarian Universalist, New York City.
Holmes graduated from Harvard University, Phi Beta Kappa. His grandfather, John Cummings Haynes, manager of the Oliver Ditson music publishing house, helped pay his Harvard tuition.
Holmes was ordained in 1904, and became minister of the Unitarian Third Congregational Church, Dorchester, Massachusetts. In February 1907, he became junior minister at the Church of the Messiah in New York City.