Navajo Livestock Reduction Act By ali.gator Aug 1, 1864 The Long Walk and the Beginning of the Incarceration at Fort Sumner Jan 1, 1920 Colorado River Compact Jan 1, 1928 Navajo Informed that Federal Government Wanted to Limit Livestock Herds Jan 1, 1928 Herbert Hoover gets authorization for Colorado River Project Oct 29, 1929 Black Tuesday and the Start of the Great Depression Jan 1, 1931 Construction on Hoover Dam Begins Affected by soil erosion in nearby Navajo Reservation Jan 1, 1933 John Collier Appointed Commissioner of Indian Affairs Jun 14, 1934 Boundaries of Navajo Reservation Extended Further into AZ & NM Jun 18, 1934 Indian Reorganization Act Passed by Congress . Sep 1, 1934 US Government Begins Buying Sheep in NM Jan 1, 1935 Navajo Reject the IRA Associated with Livestock Reduction