The small Aurach river gurgles through the heart of Herzogenaurach, population 24,000, and gives the town its name. But this peaceful, meandering waterway once symbolized a bitter, protracted family feud that divided the town into two distinct camps.

It was all about footwear.

"The town became known as the town where people tend to look down because you'd always tend to look at shoes the person is wearing before you strike up a conversation," said Barbara Smit, a Dutch financial journalist and one of the authors to tackle the story of the Dassler brothers, Rudolf and Adolf.

They started out making shoes together before having a terrible falling out. Their argument resulted in the creation of two sports giants, Puma and Adidas, both still based in the provincial town.

Partners, then enemies

Rudolf and younger brother Adolf, Rudi and Adi to friends, began their shoe business in their mother's laundry room in the 1920s. At the time, electricity supplies in the town were unreliable, and the brothers sometimes had to use pedal power from a stationary bicycle to run their equipment.

"They were very different characters," said Smit. "Adi Dassler was always more thoughtful, a craftsman who enjoyed nothing more than fiddling with his shoes. Whereas Rudolf Dassler was a more abrasive, loudmouthed salesman. They complemented each other very well to begin with."

Their new, lightweight sports shoes began to attract attention and they moved into a location south of the Aurach river near the train station.

The Dassler Brothers Shoe Factory jumped onto the world stage in 1936 when they found themselves providing footwear for American Jessie Owens, who won four gold medals at the Berlin Olympics.

But after the war, the fraternal relationship fell apart. In Smit's book, "Pitch Invasion," she theorizes that it could have had something to do with Nazi party links and that after Rudolf was picked up by American soldiers and accused of being a member of the SS, he was convinced that his brother had turned him in. Others speculate it could have had something to do with their wives, or a simple misunderstanding in a bomb shelter. No one really knows for sure.

What is certain is that they felt they could no longer work together and in 1948 the Dassler Brothers Shoe Factory was split in two.

"More of less in the middle of the night, Rudolf Dassler packed his bags and moved on the other side of the little river," said Smit. "He established Puma on the other side. From there on in, the town was really split in two like a sort of mini Berlin with this little river as a partition in the middle."

And like Berlin's famous wall, it wasn't advisable to cross over, at least when it came to shoes.

Brand loyalty became paramount for many residents. Two camps formed, and dug in.

There were stores, bakers and bars which were unofficially known as either loyal to Rudolf's Puma, or to Adolf's new company, Adidas, which he named using his nickname, Adi, and the first three letters of his last name. There were two soccer teams: the ASV Herzogenaurach club wore the three stripes; the 1 FC Herzogenaurach had the jumping cat on its footwear. Intermarriage was frowned upon.

"I knew a butcher who played for the Puma team," said Ernst Ditrich who works at the town's museum. "He told us the guys from the Adidas team didn't need to bother buying at his store. He didn't want to do business with them. That sort of thing happened."

Wayward son

The brothers never did reconcile. While they are buried in the same cemetery, their graves are about as far apart as possible. But one of their descendents decided the family feud had gone on long enough.

Frank Dassler is the grandson of Rudolf Dassler and grew up living and breathing Puma. Growing up, he had no contact at all with his great-uncle Adolf's family.

"They stayed kind of enemies during the rest of their lives," he said. "It's certainly sad, but from a business point of view it was a good decision, since it motivated both companies to innovate."

But these days, Frank Dassler sits not in Puma's new glass-and-steel headquarters on the bank of the river, but in an office at the Adidas campus further north, on the site of a former American army barracks. Two years ago, he took a job as the Adidas Group's head legal counsel.

"My stepmother and my stepbrother weren't very happy about this decision, they thought it would be a betrayal against my grandfather," he said.

His taboo breaking raised more than a few eyebrows in the town and the local newspapers were not always so kind.

"But this rivalry was years ago, it's history now," he said.

Lost its punch

Indeed, young people today seem little concerned with the once-intense rivalry.

"It's not so strong anymore. It was like that before, but now, I don't think people care so much," said 14-year-old Teresa, who was wearing Puma shoes but carrying an Adidas bag. "Sometimes Puma has something better, sometimes Adidas. It just depends."

But Hermann Lindner, 41, who was with his family (all wearing Puma) at a festival for the Argentinian team who is staying in the town for the World Cup, says the two camps haven't entirely folded up their tents.

"No, it's not as extreme as it used to be, but you still find people who stick to Puma and other who only wear Adidas," he said. "People do make the distinction."

And while most think things are better now that rivalry has cooled, some knew how to make the most of it when it was raging, Frank Dassler says. He remembers that when handymen would come to work at his grandfather's house, they would sometimes wear Adidas shoes on purpose. When Rudolf would see their footwear, he'd tell them to go to the basement and pick out a pair of Puma shoes, which they could have for free.

"Rudolf simply couldn't stand the fact that someone was wearing an Adidas shoe in his private home," Dassler said.