sentences:  The groundwork toward this declaration began in 1923 and 1925 with the works of Haudenosaunee Chief Deskaheh and Māori T.W.Ratana, who attempted to bring issues of Canada and New Zealand's failure to uphold treaties to the League of Nations, United Nations' precursor.Issues of Indigenous Peoples on a world scale began to be reevaluated in 1982 with the establishment of the Working Group on Indigenous Peoples, formed by the Economic and Social Council (ECOSOC).