Historians studying women's roles in the West have critiqued Russell's portrayal of women. They note the contrasting levels of sensuality in his depictions of white and native women, as he seemed to transfer sexuality from white to Native women, so as to conform to the moral standards and perceptions of women in his time. Most of Russell's portrayals of white women are shown as "pure" and non-sexual, other than those paintings specifically depicting prostitutes. In contrast, his series of five "Keeoma" paintings and related images show a sensual native woman. They are documented by the statement that Keeoma was a real woman whom Russell had loved. Photographs exist that show the body model for these images was Russell's wife, Nancy. Critics say that by serving as a model, she could express her sexuality in a way generally not allowed "decent" white women of the time.