[3][page needed] This led to increased calls for abolition in America, supported by members of the U.S. Congress from both the North and the South, as well as President Thomas Jefferson.
[4] At the same time that the importation of enslaved Africans was being restricted or eliminated, the United States was undergoing a rapid expansion of cotton, sugarcane, and rice production in the Deep South and the West.
Enslaved people were treated as a commodity by owners and traders alike, and were regarded as the crucial labor for the production of lucrative cash crops that fed the triangular trade.
[11] In the antebellum years, numerous individuals who escaped from slavery wrote about their experiences in books called slave narratives.
The historian E. Franklin Frazier, in his book The Negro Family, stated that "there were masters who, without any regard for the preferences of their slaves, mated their human chattel as they did their stock.
In this way, enslaved people could be bought and sold as chattel without presenting a challenge to the religious beliefs and social mores of the society at large.
[citation needed] In a study of 2,588 slaves in 1860 by the economist Richard Sutch, he found that on slave-holdings with at least one woman, the average ratio of women to men exceeded 2:1.
[clarification needed][14] Ned Sublette, co-author of The American Slave Coast, states that the reproductive worth of "breeding women" was essential to the young country's expansion not just for labor but as merchandise and collateral stemming from a shortage of silver, gold, or sound paper tender.
He concluded that enslaved people and their descendants were used as human savings accounts, with newborns serving as interest that functioned as the basis of money and credit in a market premised on the continual expansion of slavery.
They distinguish systematic "breeding"—the interference in normal sexual patterns—by enslavers with an aim to increase fertility or encourage desirable characteristics—from pronatalist policies, the generalized encouragement of large families through a combination of rewards, improved living and working conditions for fertile women and their children, and other policy changes by masters.