Zitkala-Ša was one of several women in the SAI who advocated for women's right to vote, including Laura Cornelius Kellogg, a poet and a citizen of the Wisconsin Oneida nation, and Marie Bottineau Baldwin, who was a member of the Turtle Mountain Band of Chippewa and one of the first Native woman to graduate from law school in the US. Zitkala-Ša's suffrage activism became most visible when she moved to Washington, D.C. in 1917 to become the secretary of the SAI, and when she became most active with the mainstream white suffrage movement. Her earlier writings and her visibility from testifying before Congress on Indian appropriation bills made her known to women's groups in the capital. She spoke at the National Woman's Party headquarters in June 1918 and certainly saw their pickets of the White House that intensified over the summer as she lived just three blocks away from Lafayette Park. She was also known to other groups like the Women's Christian Temperance Union, the Anthony League, and the Congressional Club, a group made up of the wives of Congressmen, who also invited her to speak and were often seeking presentations about traditional Indian life. Taking advantage of their interest, she deliberately wore what she called her "drawing card," a buckskin dress with Indigenous accessories, but then used her presentations to emphasize the concerns of "the Indian woman of today."
She educated her audiences, informing them the reservation superintendents "tyrannical powers" over a "voiceless people" who had no say in how their land or money was managed. There were many other "trials [and] dangers" around the poor education imposed on Native children at government schools, as well as Indians' lack of citizenship, which kept them from being able to address those very issues. She emphasized the irony that the "First Americans" lacked the rights all other Americans had. She also drew their attention to the thousands of Native men, including her husband, who were fighting for the country during the Great War, but were still legally classified as wards of the government, not citizens. Calling on white Americans to help change this state of affairs, Zitkala-Ša argued that US citizenship and the enfranchisement of Indians -- both women and men -- was the solution. Indian Country was and is diverse, so it is important to note that not all Indigenous people agreed with Zitkala-Ša and the other Native people advocating for citizenship and suffrage. Many tribal leaders, like those of Zuni Pueblo, believed (and indeed had been explicitly told by US government officials) that if they agreed to US citizenship and participated in elections, they were giving up their rights as sovereign nations, especially their rights to tribal land and resources. Many members of the Haudenosaunee Confederacy rejected US citizenship and emphasized their belonging in their own nations that predated the United States. In 1923, members of the Mohawk Nation traveled to Europe hoping to convince the League of Nations to recognize them as a sovereign nation. Though they were unsuccessful, they have continued to insist on their sovereignty. Also, rather than engage in conversation with white women, many Native women chose to work within their communities, helping women by serving as midwives, maintaining their languages, and carrying on cultural traditions.