From The Warmth of Other Suns, by Isabel Wilkerson:
Planters blamed northern recruiters, who were getting paid a dollar a head to deliver colored labor to the foundries and slaughterhouses of the North. But that only held for the earliest recruits, usually young men, field hands, with nothing to lose. Others said the Chicago Defender seduced them. But they could only be seduced if there was some passion already deep within them.