From 1619 to 1808 slaves were imported to the colonies. The first "20 and odd Africans" were captives removed from the Portuguese slave ship, San Juan Bautista by the privateer English warship, White Lion with Captain Jope. The slaves were destined for Mexico but commandeered in 1619 and taken to Jamestown.
This importation of slaves continued for almost two hundred years. The Slave Trade Act of 1794 was a law passed by the United States Congress that limited American involvement in the international slave trade. It was signed into law by President George Washington on March 22, 1794. In 1808 a federal law was finally passed Prohibiting Importation of Slaves and making it a crime.
The DOMESTIC slave trade within the U.S. was unaffected by the 1808 law. By 1860 there were 3,953,760 slaves in the United States (as reported to the census). The census of 1860 was the last in which much of Southern wealth was held as slaves—still legally considered property.