The humble raisin: it’s hard to imagine that dried grapes are at the center of one of the longest running business wars in the United States. But with almost all of the country’s raisins coming from a small area in California’s Central Valley, it is a brutal and cutthroat industry.In the early 20th century a few wealthy raisin growers decided to form a collective called Sun-Maid. After the government mandated that 85% of growers join the collective, Sun-Maid executives used violence and intimidation to get farmers to join. The farmers who held out had little bargaining power and were forced to accept lower prices. But in the 1960s, the independent farmers banded together to fight back. They founded the Raisin Bargaining Association to negotiate higher prices, setting off a power struggle that would last for decades.Support us by supporting our sponsors!Quartz - Just go to QZ.com for 50% off membership and enter code BW. And our friends at LinkedIn are back with a new season of Hello Monday with Jessi Hempel. Listen wherever you listen to Business Wars.