How did reliance on plantation agriculture affect the southern colonies? were their societies relatively “loose” because they were primarily rural or because they tended to rely on forced labor systems?

Over reliance of Southern colonies on agriculture greatly helped in institutionalizing slavery. As such, government agencies emerged to safeguard this important institution. This in turn led to creation of a racial hierarchy with White land owners at the top and African slaves at the bottom. This also implied less industrialization for the colonies. The southern societies were relatively "loose" since plantation agriculture kept things simple and clear. 

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