Ella Cara Deloria (January 31, 1889 – February 12, 1971), also called Aŋpétu Wašté Wiŋ (Beautiful Day Woman), was a Yankton Dakota (Sioux) educator, anthropologist, ethnographer, linguist, and novelist.

Her full siblings were sister Susan (also known as Mary Sully)[7] and brother Vine Victor Deloria Sr., who became an Episcopal priest like their father.

[6][9] She went on to become "one of the first truly bilingual, bicultural figures in American anthropology, and an extraordinary scholar, teacher, and spirit who pursued her own work and commitments under notoriously adverse conditions.

[2] In addition to her work in anthropology, Deloria had a number of jobs, including teaching dance and physical education at Haskell Indian Boarding School,[6] lecturing and giving demonstrations on Native American culture, and working for the Camp Fire Girls and for the YWCA as a national health education secretary.

[11] She held positions at the Sioux Indian Museum in Rapid City, South Dakota, and as assistant director at the W.H.

Deloria met Franz Boas while at Teachers College, and began a professional association with him that lasted until his death in 1942.

For her work on American Indian cultures, she had the advantage of fluency in the Dakota, Lakota, and Nakota dialects of Sioux,[14] in addition to English and Latin.

Boas had asked Deloria to substantiate his findings (...) She became critical of Walker’s work when she discovered that he had failed to separate creative fiction from traditional stories.

This project opened the door for Deloria to receive more speaking engagements, as well as funding to support her continued important work on Native languages.

[18] Deloria believed she could make an important contribution to their effort for recognition by studying their distinctive culture and what remained of their original language.

In her study, she conducted interviews with a range of people in the group, including women, about their use of plants, food, medicine, and animal names.