Born on May 20, 1866, in Norfolk, Virginia, Ernest Milmore Stires was the son of Van Rensselaer West Stires and Lettie M. Milmore. He attended the University of Virginia, graduating with a Bachelor of Letters in 1888. He was ordained to the diaconate in 1891 and to the priesthood in 1892. In 1894, Stires married Sarah McKinne Hardwick, and the couple went on to have four children.
Between 1891 and 1901, Stires served and led four different parishes across Virginia, Georgia, and Illinois. He moved to New York in 1901 to serve as the rector of St. Thomas Church in New York City, a position he held until 1925. Over his career, his academic achievements were recognized with several honorary doctorates, including a Doctor of Divinity from Virginia Theological Seminary (1901), a Doctor of Humane Letters from Kenyon College (1903), and Doctors of Laws from New York University, Civil Law from the University of King’s College, and Sacred Theology from Columbia University, all awarded in 1926.
In May 1925, Stires was elected Bishop Coadjutor of Long Island. However, by the time of his consecration on November 24, 1925, the incumbent bishop, Frederick Burgess, had died in office, resulting in Stires immediately becoming the third Bishop of the Episcopal Diocese of Long Island. He was consecrated by Presiding Bishop Ethelbert Talbot at St. Thomas Church in New York City. Bishop Stires led the diocese until his retirement in 1942. He died at the age of 84 in Palm Beach, Florida, on February 12, 1951, and was laid to rest in Kensico Cemetery in Valhalla, Westchester County, New York.