We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.

Slavery in America:

The history of slavery in the United States began soon after Europeans first settled in what became the United States.
From about the 1640s until 1865, people of African descent were legally enslaved within the boundaries of the present U. S. mostly by whites, but also by a comparatively small number of American Indians and free blacks.

The wealth of the U.S. was greatly enhanced by the exploitation of African American slaves.

While estimates of the number of slaves brought to North America vary from a few hundred thousand to a few million, the slave population in the U.S. had grown to 4 million by the 1860 Census. In other countries, the slave population barely reproduced itself. From the later 18th century, and possibly before that even, and until the Civil War, the rate of natural growth of North American slaves was much greater than for the population of any nation in Europe, and was nearly twice as rapid as that of England.