None of the executed slaves had killed any whites because the uprising had been foiled before it began.[144] An additional 50 slaves charged for their role in the planned rebellion would be spared, as a result of pardons, acquittals, and commutations. One reason for this was influence of a letter Monroe received from Thomas Jefferson urging mercy, telling him "The other states & the world at large will for ever condemn us if we indulge a principle of revenge, or go one step beyond absolute necessity. They cannot lose sight of the rights of the two parties, & the object of the unsuccessful one."Only seven of the executions carried out against the rebels occurred after Monroe received Jefferson's letter.[145]
Monroe was active in the American Colonization Society, which supported the establishment of colonies outside of the United States for free African Americans. The society helped send several thousand freed slaves to the new colony of Liberia in Africa from 1820 to 1840. Slave owners like Monroe and Andrew Jackson wanted to prevent free blacks from encouraging slaves in the South to rebel. Liberia's capital, Monrovia, was named after President Monroe.