st decades of the republic was that the southern states expected acknowledgment of the validity of slavery. Antislavery states expected to that when the slave entered their borders he or she was free from that moment.
Whether freedom extended after slave and/or master left the free state was complicated. The level of slave personhood was another complication. If slaves were property, they were commerce; if they were not, they were persons. On the other hand, northern states as a whole were reluctant to grant that slaves, even if persons, were citizens. Meanwhile, policies toward slaves differed from state to state. The most vigorous antislavery state during the antebellum period was Massachusetts, while the Northern state acknowledging southern states' rights was Illinois. Each court case court became more complex than the last, with the inevitable result that "the legal harmony of the nation's first five decades was about to end" (Finkelman 100). Indeed, given the federal system, it could only end in constitutional crisis.
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