Final answer:
In 1969, activists from the American Indian Movement occupied Alcatraz Island to protest against U.S. government policies and advocate for self-determination and the establishment of a cultural center. Subsequently, AIM also led the 1973 Wounded Knee Occupation to demand self-determination for the Lakota Sioux and address their mistreatment.
Step-by-step explanation:
In 1969, the American Indian Movement (AIM), symbolizing the modern Native American civil rights struggle, orchestrated the occupation of Alcatraz Island. This event was a pivotal moment in the push for self-determination and economic opportunities for Native Americans. The occupiers of Alcatraz, mainly comprised of AIM activists, envisioned the establishment of a cultural center to include a museum and other facilities reflective of American Indian heritage. The act of occupation was not only a demonstration of cultural preservation but also a protest against the federal government's termination policies. Over time, the activists' numbers grew, peaking at around four hundred individuals, before the last occupiers were removed in 1971.
In a subsequent, more radical demonstration, AIM led the Wounded Knee Occupation in 1973 at the site of a tragic 1890 massacre. The 71-day standoff drew attention to the mistreatment by federal and local agencies and emphasized the unsafe living conditions on reservations. This protest at Pine Ridge Indian Reservation demanded an end to the perceived harassment of AIM members, self-determination for the Lakota Sioux, and control over treaty-granted lands.