<Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The Fugitive Slave Law or Fugitive Slave Act was passed by the United States Congress on September 18, 1850, as part of the Compromise of 1850 between Southern slave - holding interests and Northern Free - Soilers . </P> <P> The Act was one of the most controversial elements of the 1850 compromise and heightened Northern fears of a "slave power conspiracy". It required that all escaped slaves, upon capture, be returned to their masters and that officials and citizens of free states had to cooperate . Abolitionists nicknamed it the "Bloodhound Law" for the dogs that were used to track down runaway slaves . </P> <Table> Events leading to the American Civil War <Tr> <Td> <Ul> <Li> Slavery </Li> <Li> Northwest Ordinance </Li> <Li> Kentucky and Virginia Resolutions </Li> <Li> Battle of Negro Fort </Li> <Li> Missouri Compromise </Li> <Li> Tariff of 1828 </Li> <Li> Nat Turner's slave rebellion </Li> <Li> Nullification Crisis </Li> <Li> The Amistad </Li> <Li> Prigg v. Pennsylvania </Li> <Li> Texas annexation </Li> <Li> Mexican--American War </Li> <Li> Wilmot Proviso </Li> <Li> Manifest destiny </Li> <Li> Underground Railroad </Li> <Li> Nashville Convention </Li> <Li> Compromise of 1850 </Li> <Li> Fugitive Slave Act of 1850 </Li> <Li> Uncle Tom's Cabin </Li> <Li> Kansas--Nebraska Act </Li> <Li> Ostend Manifesto </Li> <Li> Bleeding Kansas </Li> <Li> Caning of Charles Sumner </Li> <Li> Dred Scott v. Sandford </Li> <Li> The Impending Crisis of the South </Li> <Li> Brown's raid on Harpers Ferry </Li> <Li> 1860 presidential election </Li> <Li> Crittenden Compromise </Li> <Li> Secession of Southern States </Li> <Li> Star of the West </Li> <Li> Corwin Amendment </Li> <Li> Morrill Tariff </Li> <Li> Battle of Fort Sumter </Li> </Ul> </Td> </Tr> <Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> </Table>

What was a requirement of the fugitive slave act
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