Eleanor Percy Ware was born in Natchez, Mississippi in 1819, the second daughter of Sarah Percy and her second husband Major Nathaniel Ware, an attorney and aide to the Mississippi territorial governor. (Sarah was the widow of Judge John Ellis, who died in 1808. They had a son Thomas and a daughter Mary Jane Ellis together.) Eleanor's older sister was Catherine Anne Ware. Sarah Percy was from a prominent Southern family with a noted vulnerability to mental illness. She was 39 when Eleanor was born and suffered from post-partum depression following the birth. She never fully recovered.