http://www.law.du.edu/russell/lh/alh/docs/dawesact.html The Dawes Act] URL last accessed 2006-11-18 Between the years 1887 (the year the Dawes Act came into effect) and 1934 (known as the "Allotment era") the government took over 90 million acres of tribal lands that were previously guaranteed to tribes by treaties and federal law.