Slaves were introduced into N.Y. as early as 1626 when the West India Co. (a Dutch company), which had large establishments on the coast of Guinea, brought negroes to Manhattan, and practiced the slave trade here "without remorse."
It is said that in proportion to population N.Y. imported as many Africans as Virginia. That New York did not become a slave-state like Carolina was, according to Bancroft, "due to climate and not to the superior humanity of its founders. [Gov.] Stuyvesant was instructed to use every exertion to promote the sale of negroes.
They were imported sometimes by way of the West Indies, often directly from Guinea, and were sold at auction to the highest bidder. The average price was less than $140." With the extension of English rule to N.Y. in 1664 the slave trade in this colony passed into the hands of the British. It is estimated that the total import of slaves into all the British colonies of America and the West Indies from 1680 to 1786 was 2,130,000.
The traffic was then carried on principally from Liverpool, London and other English ports; the entire number of ships sailing from these ports then engaged in the slave traffic was 192, and in them space was provided for the transport of 47,146 negroes.
The native chiefs on the African coasts took up the hunt for human beings and engaged in forays, sometimes even on their own subjects, for the purpose of procuring slaves to be exchanged for western commodities. They often set fire to a village by night and captured the inhabitants when trying to escape. Out of every lot of 100 shipped from Africa, about 17 died either during the passage or before the sale at Jamaica, while not more than 50 lived through the "seasoning" process and became effective plantation laborers.
Slavery in N.Y. was continued till 1827. It was then abolished by terms of an act passed by the N.Y. Assembly ten years earlier.
source: THE GREATEST HIGHWAY IN THE WORLD Historical, Industrial and Descriptive Information of the Towns, Cities and Country passed through between New York and Chicago via The New York Central Lines