Answer:
Slavery spread rather than grew because it was an agricultural rather than industrial form of capitalism, so it needed new lands. And slavery spread because enslaved African Americans were forced to migrate.During the 17th and 18th centuries people were being held captive from the continent of Africa, forced into slavery in the American colonies and utilized to work as apprenticed servants and labor in the production of crops such as tobacco and cotton.
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This is how did slavery develop in america in my own words