Popular narratives attribute poverty on Native American reservations today to historical resource expropriation and the resulting dearth of high-quality land, but the analysis here shows the narrative is incomplete. Combining data on rainfall, soil quality, and income shows that reservations with small shares of prime agricultural land generated higher incomes than reservations with larger shares over 1970 to 2010. We attribute this finding to the way in which land privatization legislation was implemented on reservations from 1887 to 1934. Reservations with the poorest land were not allotted, whereas reservations with higher-quality lands were partially privatized such that allotted lands remained under federal trusteeship. The hypothesis that land quality indirectly reduced income generation, through its effects on land tenure, is supported by our finding that land quality positively affects income after accounting for land tenure. We conclude that reservation poverty is, at least in part, due to top-down land policies.