Fall of Sentra
As Sentra pushed further east, they began to encroach on the Dwarven Entente. Some cooler heads tried to prevent another war, but to the xenophobic dwarves and hot-headed humans, the conflict seemed inevitable. The Fall of Sentra—as the non-human races call it—or the Dwarf Wars—as the Sentrans call it—began with an unexpected encounter between a human brigade from the town of Byroad and dwarven skirmishers.
But the Sentrans were not unprepared. They had a vaunted army made of advanced golems called Automatons ready to support the already large army. But something unexpected happened, as some of the Automatons began to turn against their masters. In order to protect its citizens, forces sent to protect the frontier from the demihumans were pulled towards the inner Empire to break the mutinous Automatons. More than one Sentran faction tried to take advantage of the situation for their own benefit.
But it was not the end of the human's problems. Encroaching barbarians to the north, the dwarves to the east, and corsairs along the southern coasts harassed and assaulted the Sentran armies. The northern barbarians, human and gnomes alike, were united under a single charismatic leader.
The provinces furthest from the Empire's control began to slip out of their control. Without the protection of the army, the benefits of Sentra seemed less appealing. Independent deals were struck with these borderland provinces amongst themselves and their demihuman neighbors.
The Automatons were eventually destroyed, melted down into pieces. The Sentran army was free to return to the borders, only to find themselves not just fighting against demihumans, but provinces that were once part of the Empire.
The Empire did not go with a whimper or a bang, but slowly over several years. Although still a power on the continent, it never fully recovered. To the imperials, this time is simply known as the Calamity, but most historians refer to it as the Fall of Sentra.