It is a huge misconception that there were no slaves in the north. Slavery was not as common due to the fact that the Northern economy was not as heavily agricultural as in the South. New York and Connecticut had large slave populations. <span> In the North they have cold winters and the South had mild winters. Meaning you would have to provide warmer cloths, food and warmer shelter which would cost slave owners in the North more money</span>
The east-west trade routes between Greece and China began to open during the first and second centuries B.C. The Roman Empire and the Kushan Empire (which ruled territory in what is now northern India) also benefitted from the commerce created by the route along the Silk Road.