The Great Sioux War was a massive genocide campaign done by the United States of America from 1865 to 1867. It was sparked mostly by the thirst for blood after the U.S' humiliating defeat in the War Between The States, as well as President Fremont's need to further Manifest Destiny, now that all of Canada belonged to the American nation. The War lasted for two years before the surrender of the Provisional Metis/Sioux leadership at Little Big Horn.