Slavery had been legally practiced in America ever since the states were colonies of the British Empire. The first slaves were brought to American soil as early as the 1600s by Dutch ships, but the practice became widespread throughout the 18th and 19th centuries. It is estimated that about 6-7 million slaves were brought to the American colonies from Africa in the 18th century.
By the time of the War of Independence, the North states no longer relied on slaves because they were more industrialised than the South. This is when the first calls to end slavery appeared. Colonists in the North associated the oppressive institution of slavery with how they were oppressed by the British Empire.
Nevertheless, slavery remained legal even after the United States became independent, and it was accepted by the new Constitution. This was mainly because owning slaves meant paying more taxes to the states, and it was, therefore, a way for the local, state governments to collect more money from the population.
In the years succeeding American independence, Southern states began cultivating more cotton a...