The American Indian Movement (AIM) was founded at a time of continuing social change and protest following achievement of national legislation of the civil rights movement. The radical approach AIM adopted was based on its leaders' perceptions that early Indian advocacy had failed to achieve any tangible results by lobbying activities with Congress and state legislatures. AIM used the press and media to present its own unvarnished message to the American public. During ceremonies on Thanksgiving Day 1970, commemorating the 350th anniversary of the Pilgrims' landing at Plymouth Rock, AIM seized the replica of the Mayflower. In 1971, members occupied Mount Rushmore; in 1972, they marched the "Trail of Broken Treaties" and took over the Bureau of Indian Affairs (BIA) headquarters in Washington, D.C. In February of 1973, a group of AIM members took part in a seventy-one days long siege at Wounded Knee, South Dakota. The occupation was in response to the 1890 massacre of at least 150 Lakota Sioux men, women, and children by the U.S. Seventh Calvary at a camp near Wounded Knee Creek. During the siege, AIM occupied the Sacred Heart Church and the Gildersleeve Trading Post. Although periodic negotiations were held between AIM spokesmen and Federal government negotiators, there was shooting from both sides. This collection includes the extensive FBI documentation on the evolution of AIM as an organization of social protest. In addition, there is documentation on the 1973 Wounded Knee Stand-off. Informant reports and materials collected by the Extremist Intelligence Section of the FBI provide unparalleled insight into the motives, actions, and leadership of AIM and the development of Native American radicalism.