The abolition of the transatlantic slave trade to the United States was the result of proscribing the traffic step by step. It was determined by complex contingent factors and not by a wave of anti-slave trade campaigning. This was partly because the attack on the slave trade moved at different paces in various parts of North America; partly because of the location of political sovereignty; and partly because the issue of the slave trade was bound up with broader concerns over slavery and politics in the transition from the thirteen British colonies in North America to the new federal nation. Quakers, emphasising moral and humanitarian arguments against the slave trade, made significant inroads into banning the slave trade in Pennsylvania and New Jersey in the generation before the American Revolution, and their influence later spread throughout the northern colonies and states and into the Chesapeake by the 1780s. But the Quaker anti-slave trade stance did not spread sufficiently among other groups in North America to produce widespread disapprobation of the Guinea traffic by the time of the American revolutionary war. Thus, there was no national consensus against the slave trade when the United States was created.