The family feud turned out to be pretty good for business.

"As embittered rivals, the estranged brothers led their respective companies to the top of the world," writes Barbara Smit in her book Sneaker Wars. "Muhammad Ali, Franz Beckenbauer and Zinédine Zidane became legends in the 3 stripes of Adidas, while soccer god Pelé and Boris Becker achieved global fame in Pumas."

After acquiring Reebok in 2005, Adidas significantly expanded its global reach into North American markets, where it's second only to Nike (NKE). In addition to its world-famous shoes, Adidas now manufacturers apparel for tennis, golf, basketball, lacrosse and an array of accessories including bags, socks, watches, hats, and even deodorants.

While Puma still stands in the shadow of Adolf’s business, the company has seen rapid growth over the last 10 years. In 2006, the company clinched sponsorship of the World Cup, and brought on New York Yankees all-star center fielder Johnny Damon as its US spokesman.

Only once has a truce been documented - although among the die hards it may be seen as more of a defection. Frank Dassler, the grandson of Rudolf, was at one time the head of Puma USA. He is now the head of legal affairs of Adidas.

In an interview with Newsweek, Smit said that Frank’s crossing of the river ultimately “symbolizes that things are a bit more rational these days.”

Indeed, the complicated world of international business may have driven Dassler to unite the clans, albeit briefly. But for the original combatants, Adolf and Rudolf, the feud remains eternal.

As BBC writer Tom Hagler observes: “At the local cemetery, their graves are about as far apart as you can get.”