Human use of land has been transforming Earth's ecology for millennia. From hunting and foraging to burning the land to farming to industrial agriculture, increasingly intensive human use of land has reshaped global patterns of biodiversity, ecosystems, landscapes, and climate. This review examines recent evidence from archaeology, paleoecology, environmental history, and model-based reconstructions that reveal a planet largely transformed by land use over more than 10,000 years. Although land use has always sustained human societies, its ecological consequences are diverse and sometimes opposing, both degrading and enriching soils, shrinking wild habitats and shaping novel ones, causing extinctions of some species while propagating and domesticating others, and both emitting and absorbing the greenhouse gases that cause global climate change. By transforming Earth's ecology, land use has literally paved the way for the Anthropocene.