In the decade before the California Gold Rush, the popular idea that Americans held a natural right to land as a legacy of the American Revolution was enriched and expanded by such events as the Dorr Rebellion in Rhode Island, the Anti-Rent War in New York, the flood of Irish refugees into New York City, growing opposition to the expansion of slavery into new territories acquired during the war with Mexico, and the Revolution of 1848 in Europe. These events strengthened popular sovereignty and the notion that human beings had rights that transcended those defined by legislatures, courts, or even constitutions. They also promoted a new discussion of how values within the United States differed from those in Europe--where land was scarce and served as the foundation for aristocratic regimes and sharp class differences. The squatter was a ubiquitous figure on every frontier of the United States, but none more than California, where both town sites and agricultural land were covered by Mexican land grants that took decades to define and confirm. This article tells the story of how powerful forces in California undermined squatter rights--and the heritage of the American Revolution as well.