TED: The rise and fall of the Lakota EmpireIn 1776, a powerful empire was born in North America. The Lakotas had reached the Black Hills, the most sacred place and most coveted buffalo hunting grounds in the western plains. Located in what is now South Dakota, control of the Black Hills, or Paha Sapa, marked the tribe as the dominant power in the American West. Pekka Hämäläinen explores the rise and fall of the Lakota Empire.