There were only 22,492 such persons in Pennsylvania in 1810, but in 1820 there were 30,202, and in 1830 as many as 37,930.

This number increased to 47,854 by 1840, to 53,626 by 1850, and to 56,949 by 1860.

The undesirable aspect of the situation was that most of the migrating blacks came in crude form.[9] "On arriving," therefore, says a contemporary, "they abandoned themselves to all manner of debauchery and dissipation to the great annoyance of many citizens."[10] Thereafter followed a number of clashes developing finally into a series of riots of a grave nature.

Innocent Negroes, attacked at first for purposes of sport and later for sinister designs, were often badly beaten in the streets or even cut with knives.

The offenders were not punished and if the Negroes defended themselves they were usually severely penalized.