The Atlantic Slave Trade was one of, if not the largest, large-scale movement of human beings from one part of the world to another by sea and could have been considered a mobile killing machine due to the horrific conditions. The numbers were so large that slaves from the slave trade were the largest number of Old World immigrants in the world. Although there were only races of people enslaved during the Atlantic slave trade, African Americans were the most numerous. Records show 34,941 voyages during the slave trade period. The transatlantic slave trade took place across the Atlantic Ocean in the 16th century and lasted until the 19th century. The way the Atlantic slave trade happened was cruel but not unthinkable. The capture and enslavement of African Americans was inevitable, the only question was when. Many more slaves were brought to South America than to North America because the South “needed” them more. The South Atlantic economic system was based on producing crops, producing goods and other things to sell. The slaves didn't just board the ship with smiles on their faces. The Spanish colonists asked the King of Spain for permission to bring slaves to the New World to provide for them. The Spanish colonists were currently forcing the Native Americans to do their work for them, but they were dying in large numbers due to disease and the colonists' lack of care. The King of Spain gave approval for the colonists to import Africans and thereafter Africans were transported there for the use, labor and other needs of the Spanish colonists. Many African American slaves were transported during this period. An estimated twelve to fifteen million African Americans were shipped around the world, including…half of paper…, to Virginia, in 1619. These first kidnapped Africans were classified as indentured servants and freed after seven years. Chattel slavery was codified in Virginia law in 1656, and in 1662 the colony adopted the principle of partus sequitur ventrem, under which the children of slave mothers were slaves, regardless of paternity. Irish immigrants brought slaves to Montserrat in 1651, and in 1655 the slaves were shipped to Belize. In Britain, America and Portugal and in some parts of Europe, opposition against the slave trade developed. Davis states that abolitionists assumed "that the end of slave importations would automatically lead to the amelioration and gradual abolition of slavery." However, a brisk illegal trade continued to ship large numbers of slaves to Brazil and even Cuba until the 1860s, when British imposition and further diplomacy finally ended the Atlantic trade..