Final answer:
The United States increased the number of slaves through natural population growth, the domestic slave trade, smuggling, and forcing people into slavery through laws. Slaves were needed to work on plantations, build infrastructure, and work in various industries.
Step-by-step explanation:
The United States increased the number of slaves after the ban on importing slaves through various methods:
- Natural population growth: Enslaved individuals were allowed to have families, and as a result, the slave population grew naturally.
- Domestic slave trade: Enslaved people were bought and sold within the United States, especially from the Upper South to the Lower South, where the demand for labor was high.
- Smuggling slaves: Despite the ban on the international slave trade, slave smugglers brought enslaved Africans illegally into the United States, primarily through Florida, Texas, and Cuba.
- Forcing people into slavery through laws: Some states adopted laws that allowed landowners to acquire apprentices from Africa despite the ban on the international slave trade.
The United States needed so many slaves for various tasks, including:
- To work on plantations where cash crops like cotton were cultivated.
- To help build infrastructure such as roads, canals, and railroads.
- To work in various industries such as mining, manufacturing, and construction.