Benedict was born Ruth Fulton in New York City on June 5, 1887, to Beatrice (Shattuck) and Frederick Fulton. Her mother worked in the city as a school teacher, while her father was a homeopathic doctor and surgeon. Although Mr. Fulton loved his work and research, it eventually led to his premature death, as he acquired an unknown disease during one of his surgeries in 1888. Due to his illness the family moved back to Norwich, New York to the farm of Ruth's maternal grandparents, the Shattucks. A year later he died, ten days after returning from a trip to Trinidad to search for a cure.