Centuries before the Rachni Wars and the Krogan Rebellions, when Tuchanka was a wasteland suffering a Nuclear Winter. Haxten Haghar the grandfather of Jurdon Madadh, formerly known as Haxten Madadh, is getting a position as a Warlord. And trying to gain control over other Clans on Tuchanka. He managed to get some Clans together to fight against other Clans. Which nearly caused his Clan Haxten to get extinguished but his son Haxten Treagar, managed to pull it off by retreating with the remaining Krogan.
They made their camp behind a chasm which is also called the chasm. A deep abyss on Tuchanka which separates the planet in two big areas. Well during the Rachni Wars his grandfather and his father fought inside them, his father being a lot younger and also fighting in the Rebellions. After the Rebellions with the Genophage it was nearly impossible to get children, but Haxten Treagar managed to get a female which was not that much affected by the Genophage.
When Madadh was born an accident happened during the pregnancy of his mother causing her to be exposed to element zero, which caused biotic abilities later on. Let’s just say the exposure was so high that his mother nearly died when she gave birth to him. Madadh was nearly 100 years inside this Clan, he had not taken the Rite of Passage yet but another Rite. Which is why he had markings on his crest. When another now extinct Clan attacked them. They both extinguished each other on the battlefield. Leaving only a field of dead bodies behind and some survivors. Madadh made it, but not his father or his mother. With being so young, he needed the Rite of Passage, otherwise he would have been killed off.
During that time only a few Clans were really interested and he ended up being in Clan Jurdon. An enemy Clan of Urdnot. At that point Madadh had nothing against Urdnot. So he managed to get the status of a Battlemaster in Clan Jurdon, given his biotic abilities and strategic history from his father. He managed to get the Clan Jurdon across the chasm, and managed to build a bridge - so that other Clans can come across if they want. It was a peaceful life until 700 years later, he was the father of many children, especially twins from a female called Purnav, he witnessed some Krogan warriors later being claimed to be from Clan Urdnot murdering his twin children and Purnav.
Which well caused him to hate Urdnot from that day and he still hates them. A lot of people have noticed that he is the grandfather of Raik Cagar. He is fairly pissed off when her father, a Clan member from Clan Jorgal, abducted her. But when he heard, two centuries later, that she was safe, he stopped being all angry at Clan Jorgal.