When America's Founding Fathers (the country's earliest leaders) established the United States in the late 1700s, they decided to build the new nation on principles of freedom and liberty for its people. But during America's first years of existence, the country's leaders decided not to extend those freedoms to a small but growing segment of the population. The new nation's slaves, who had been removed from Africa by force or born into captivity in the "New World," were denied the rights that their white masters enjoyed, even though they contributed a great deal to America's agricultural economy. These slaves continued to be treated as property, even as the nation's white leaders were working to build an otherwise democratic government.

Many of America's early political leaders did not like slavery, but they recognized that slaves were used extensively by farmers in...