One of the most infamous events in the battle for Native American right began on February 27, 1973, when over two hundred armed activists from the Oglala Lakota tribe (many affiliated with the Native rights organization American Indian Movement, or AIM) took control of Wounded Knee, South Dakota, the town that was home to the Pine Ridge Reservation and the site of an infamous Indian massacre in 1890. The Oglala Lakota seized the town's official buildings, blocked off roads leading in and out of the city, and prepared for a stand off against federal authorities. The Oglala Lakota and the AIM held control of Wounded Knee for seventy-one days as they demanded reparation for broken treaties, changes in discriminatory policies and the removal of corrupt tribal officials. Filmmaker Stanley Nelson combines newsreel footage of the 1973 siege and new interviews with many of the key participants in his documentary Wounded Knee, which tells the story of the rise of the AIM in the late 1960's and early 1970's as well as the real-life drama of their most famous action. Wounded Knee received its world premiere at the 2009 Sundance Film Festival.