The supernatural aspect of John Henry recalled West African traditions, particularly Igbo stories about evil spirits that would have been transmitted from Africa by slaves. According to Igbo tradition, those who had died in terrible or surprising circumstances still inhabited the underground. These spirits might possess or haunt the living and needed to be warded off by various means, including singing to keep their souls at bay. Collectors who gathered, recorded, and transcribed these songs in the late 1920s mentioned their creepy, supernatural side, but fewer modern songs sounded this way.