What two phenomena led to the expansion of slavery in the south

1) The expansion into new land settlement in the South which put into use as cotton plantations

2) The growing international demand for cotton and the presence of international financing

Explanation:

With the expansion into purchased land came the business opportunity to engage in the international cotton trade and other forms of farming which required labor. Due to the increased production and demand the price of cotton fell leading to the need for more hands and for the fields.

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