Mary Jane Stoddard was the youngest of twelve siblings. Her father was a West Cornwall farmer. As a teenager, Mary Jane left West Cornwall to live with her sister, Elizabeth Huntington, wife of Collis P. Huntingon.
In 1851, she married Delos W. Emmons, a farmer in Oneonta, New York. The couple continued the farm life until the 1860s, when Collis Huntington found a use for Delos: he made him General Superintendent of the Chesapeake and Ohio Railroad and sent the Emmons family to West Virginia, where they founded the town of Huntington in 1871. Mary Jane’s new house, overlooking the Ohio River, became the hub of social life in the city she helped establish.