The Golden Divide

The social war that took apart the Golden Expanse and turned it into 5 separate petty kingdoms has been dubbed "The Golden Divide". Though once a upon a time a single nation united under a single king, The Golden Expanse ripped itself apart from the inside as each of the noble houses gained power and influence. As the king's power dwindled by the wealth and flagrant disregarded for laid laws by the 5 houses, each Noble house began to build up their own city. As walls were raised, private armies trained and funded, and pressure increased from every side, the King was forced to flee his own nation before a bloody coup could claim his life.
After the king fled, each of the houses immediately tried to claim the throne and power vacuum that formed. Sadly for the further houses, Sidca already had it's forces in the walls having been "The King's Military", and short of a siege, the throne was already claimed. Refusing to accept the new king, each kingdom begain to declare independce from the newly self appointed king, and the seniors of each house claimed themselves to be king. 
After dozens of skirmishes and boundary lines being informally laid by military might, the kingdom stabilized after nearly 12 years. Now, the Golden Expanse mselves. The political gears have been grinding even now, decades later.