In the five hundred years between Columbus and Wounded Knee, tens of millions of native peoples died from disease and conflict with European explorers and settlers. There can be no doubt that this was a genocide on every level: socially, culturally and linguistically.
In the smaller, specific context of Wounded Knee, this too was a genocide. It involved the massacre of 150 - 300 men, women and children for who they were and where they lived. It was senseless, brutal, racist and quite simply, murder. Most historians agree that the slaughter of Native Americans at the hands of the U.S. government in the 19th century is one of the darker stains on our national history.