by S.E. Schlosser

The phrase has its roots in the South, where traveling bands would play in front of political rallies, often attracting a crowd.  Since the band had the crowd’s attention, politicians and religious leaders would often jump up on top of the band wagon, interrupting the music, and give a speech to the already-attentive crowd.  This practice was usually tolerated by folks listening to the band because they knew the music would be back soon. 

People were literally jumping onto the band wagon as far back as the late 1700s, and they still are – figuratively – today!