The Reverend Colman E. O'Flaherty (24 April 1878 – 3 October 1918), was an Irish-born American Catholic military chaplain and a recipient of the Distinguished Service Cross during World War I. O'Flaherty was born in Carraroe, Ireland.

He received his early education in Ireland and continued his studies at Lyons, France where he became fluent in French and at Montreal, Canada.

He was ordained a Roman Catholic priest at Sioux Falls on 15 September 1901 and spent the next nine years at Chamberlain and Kimball during which time he was responsible for the construction of seven church buildings including Columbus College at Chamberlain.

He was posthumously awarded the Distinguished Service Cross, the citation of which read: For extraordinary heroism near Very, France, Chaplin O'Flaherty displayed conspicuous gallantry in administering to the wounded under terrific fire, exposing himself at all times to reach their sides, and give them aid.

[2] He was the older brother of Mayor of Galway Michael O'Flaherty (elected 1950) and uncle of Mayor of Galway Patrick O'Flaherty (born 1928, elected 1964).