She features in the genealogies of various 11th and 12th century versions of the Kentish Royal Legend. These describe her as the daughter of King Eorcenberht of Kent and St. Seaxburh of Ely, and wife to Wulfhere of Mercia, with whom she had a daughter, St. Wærburh, and a son, Coenred. Eormenhild became a nun after her husband died in 675, and eventually became abbess of Minster-in-Sheppey and Ely consecutively.
There are almost no contemporary records for her life. When discussing Wulfhere, Bede mentions neither she nor her daughter Wærburh. However, her name is mentioned as an abbess in a (copy of a) charter of King Wihtred of Kent, dated 699, along with three other abbesses present at the occasion when the charter was issued: "Irminburga, Aeaba et Nerienda".
Her feast day is 13 February.