The grapes for Purple Cowboy come primarily from Paso Robles, the largest appellation in San Luis Obispo on California's famed Central Coast. The Paso Robles AVA (wine region) is sometimes called Cowboy Wine Country.
The story goes that a group of young winemakers worked hard all week and tasted so much wine that their teeth turned purple. On weekends, these same men loved to rodeo. They became known as the 'Band of the Purple Cowboys'. So the legend goes.