James Mooney (February 10, 1861 – December 22, 1921) was an American ethnographer who lived for several years among the Cherokee. Known as "The Indian Man", he conducted major studies of Southeastern Indians, as well as of tribes on the Great Plains. He did ethnographic studies of the Ghost Dance, a spiritual movement among various Native American culture groups, after Sitting Bull's death in 1890. His works on the Cherokee include The Sacred Formulas of the Cherokees (1891), and Myths of the Cherokee (1900). All were published by the US Bureau of American Ethnology, within the Smithsonian Institution.

Native American artifacts collected by Mooney are held in the collections of the Department of Anthropology, National Museum of Natural History, Smithsonian Institution and the Department of Anthropology, Field Museum of Natural History. Papers and photographs from Mooney are in the collections of the National Anthropological Archives, Department of Anthropology, Smithsonian Institution.

James Mooney was born on February 10, 1861, in Richmond, Indiana, son of Irish Catholic immigrants. His formal education was limited to the public schools of the city. He became a self-taught expert on American tribes by his own studies and his careful observation during long residences with different groups. The field of ethnography was new in the late 19th century, and he helped create high standards for the work.

In 1885 he started working with the Bureau of American Ethnology (now part of the Smithsonian Institution) at Washington, D.C., under John Wesley Powell. In 1887, he moved to live among the Eastern band of the Cherokee. He compiled a list of Native American tribes that totaled 3,000 names. It ended after the US Army's 1890 massacre of Lakota people at Wounded Knee, South Dakota. Mooney became recognized as a national expert on the American Indian.

Mooney's writing style was widely considered as evocative. His sympathetic treatment of Native Americans is attributed to his upbringing and ethnic heritage. Although he wrote as a scientist, his objective attitude toward Native Americans contrasted with other writing, which was often either romantic or discriminatory. He largely accepted the goal of Indian assimilation as outlined by reformers of the era. But, he was a witness to what the costs were to the traditional peoples and reported on issues and changes with objectivity.

During the late 1800s Native Americans were under harsh attack in many areas, and essentially subjects of genocide by the United States of America. The Indian Wars, intended to suppress tribal resistance to European-American settlement of the West, was generally presented as required because Native Americans made unjustified attacks on pioneers. Mooney wrote more objectively about issues in the West.

Mooney took the time to observe various Native American tribes in the way they lived on a daily basis. Prior to his work, most people outside reservations learned about issues only from a distance. He wanted to learn and to teach other Americans about their culture. He published several books based on his studies of Native American tribes.

Mooney provides a preface with a historical survey of comparable millenarian movements among other American Indian groups. In response to the rapid spread of the Ghost Dance among tribes of the western United States in the early 1890s, Mooney set out to describe and understand the phenomenon. He visited Wovoka, the Ghost Dance prophet, at his home in Nevada. He also traced the movement of the Ghost Dance from place to place, describing the ritual and recording the distinctive song lyrics of seven separate tribes.