The migration of Negroes to northern communities was at first checked by the reaction in those places during the thirties and forties.

Thus relieved of the large influx which once constituted a menace, those communities gave the Negroes already on hand better economic opportunities.

It was fortunate too that prior to the check in the infiltration of the blacks they had come into certain districts in sufficiently large numbers to become a more potential factor.[41] They were strong enough in some cases to make common cause against foes and could by cooperation solve many problems with which the blacks in dispersed condition could not think of grappling.
Their endeavors along these lines proceeded in many cases from well-organized efforts like those culminating in the numerous national conventions which began meeting first in Philadelphia in 1830 and after some years of deliberation in this city extended to others in the North.[42] These bodies aimed not only to promote education, religion and morals, but, taking up the work which the Quakers began, they put forth efforts to secure to the free blacks opportunities to be trained in the mechanic arts to equip themselves for participation in the industries then springing up throughout the North.

This movement, however, did not succeed in the proportion to the efforts put forth because of the increasing power of the trades unions.
After the middle of the nineteenth century too the Negroes found conditions a little more favorable to their progress than the generation before.

The aggressive South had by that time so shaped the policy of the nation as not only to force the free States to cease aiding the escape of fugitives but to undertake to impress the northerner into the service of assisting in their recapture as provided in the Fugitive Slave Law.