Complex sentence: Serious debates over abolition took place in the Virginia legislature in 1829 and 1831; in the North discussion began about the possibility of freeing the slaves and then resettling them back in Africa (a proposal that led to the founding of Liberia).
Split into simpler sentences: Serious debates over abolition took place in the Virginia legislature in 1829 and 1831. In the North discussion began about the possibility of freeing the slaves and then resettling them back in Africa (a proposal that led to the founding of Liberia).