Marion Koogler McNay, art collector, philanthropist, and founder of the Marion Koogler McNay Art Museum at San Antonio, was born at De Graff, Ohio, on February 7, 1883, the only child of Dr. Marion A. and Clara V. (Lippincott) Koogler. A year later the family moved to El Dorado, Kansas, where Koogler invested in many acres of grazing land, later the source of the Koogler oil fortune, which Marion inherited at the death of her parents. She studied art at the University of Kansas (1900–1902) and at the Art Institute of Chicago. She joined her parents in their retirement in 1912 in Marion, Ohio. Her marriage to Don Denton McNay, a railway manager and sergeant in the United States Army, on December 9, 1917, ended ten months later with his death from Spanish influenza in Florida. Through four subsequent marriages and divorces she retained the name of her first husband. She was married to Charles Newton Phillips, a Marion banker, from 1921 to 1925; to Donald Taylor Atkinson, a San Antonio ophthalmologist, from 1926 to 1936; to Victor Higgins, a Chicago artist working in New Mexico, from 1937 to 1940; and to Adelbert E. Quest, a Chicago art dealer, in 1940–41. She had no children.
McNay moved to San Antonio in 1926 and after her marriage to Dr. Atkinson began construction of a Spanish colonial mansion designed by Atlee and Robert Ayres on acreage called Sunset Hills, at the intersection of Austin Highway and New Braunfels Avenue. The mansion, completed in 1929, housed her growing collection of American watercolors, French Impressionist paintings, and art objects. She herself designed some of the mansion's tiling and stenciled ceilings. She was a frequent summer visitor to Taos and Santa Fe and acquired numerous works by artists painting in the New Mexico area. Her patronage extended to the art of the Pueblo Indians, and her collection of their crafts and of primitive Spanish colonial art is part of the permanent collection of the museum.
In 1943 a proposed congressional bill provided for exploration of Pueblo lands preliminary to the construction of a dam on the Rio Grande. This project, thought by conservationists to endanger several pueblos and their shrines, was defeated largely due to Marion's efforts. In her later years McNay devoted much of her time to the directorship of the San Antonio Art Institute, the former Witte Museum School of Art, which was housed in an aviary on the grounds of her home. The San Antonio Art Institute declared bankruptcy and closed in 1990.
Although her religious background was Presbyterian, McNay was converted to Catholicism under the spiritual guidance of the Rev. Peter M. Baque. Among her many charities, the foremost was the Missionary Servants of Christ the Master and St. Anthony, a lay society of Catholic women. After Baque's death, Marion McNay commissioned Texas sculptor Karl J. (Charles) Umlauf to do a large aluminum crucifix, which was placed at the head of Father Baque's grave in the Cemetery of the Sisters of St. Anthony in San Antonio. Jessie Marion Koogler McNay died of pneumonia on April 13, 1950, in a San Antonio hospital, and was buried next to Father Baque's grave. Her bequest to the sisters was generous, but the bulk of her estate was left in trust for the conversion of her home into a museum of modern art, the first of its kind in San Antonio.