The late Bill Marvey, one of the world's last remaining manufacturer of barber poles, shared his expert opinion in a 1981 article. He explains: The symbolism of the barber pole goes back to the barber/surgeon of the Middle Ages. In addition to cutting hair, he'd pull teeth, let blood, use leeches, lance boils. He'd hang his bandages out to dry, and they'd blow in the wind and twist around red and white together.
If you needed dental work, enemas, or wound surgery during this time, the barber/surgeon was the man to visit. A pole painted red and white (to represent blood and bandages) was an advertisement to potential patients. By the 19th century, barbers began focusing on hair styling and snipping, leaving the ER work to the doctors. The distinctive striped pole remained however.
It's not quite as clear what the blue stripe of a barber pole represents. One interpretation says the blue stands for veins. Marvey believes the blue stripe was added during the turn of the century as a patriotic gesture.
