Born at Fancy Farm, Kentucky, on September 5, 1874 to James and Mary Belle Mitchell Thomas, Henrietta belonged to a large family of brothers and sisters. Her parents were strict Catholics and believed in their children learning to pray at an early age. Because of a physical illness, Henrietta had to wait 38 years to respond to her religious vocation. She entered the novitiate at Mount Saint Joseph on October 21, 1912, and took the name Sister Diomede.
Sister Diomede had only one assignment during her 35 years as an Ursuline. She remained at Mount Saint Joseph making the altar breads for the chapel and for the local parishes ‑‑ a work she dearly loved. For years, postulants and novices considered it an honor to assist Sister Diomede in this labor of love.
As a hobby, Sister Diomede grew lovely flowers, taking pride in displaying the results of her patient nurturing of plants, especially her favorite, pink geraniums. Sister Diomede lived a hidden life, however she brought the cares of the world straight to the Heart of Christ through her sense of compassion and her prayers for healing forgiveness in her sphere of influence. Death came to her on May 20, 1947. Father Gilbert Henninger, chaplain, offered the funeral Mass. Sister Diomede’s remains are buried in the convent cemetery where she had spent so much time praying among the deceased Sisters. One of her survivors was her Ursuline sister, Sister Teresa.