Atanarich's war

The thirteenth century after the founding was not a good time for the Empire, as the country was exhausted by protracted military action on most of its borders. The manpower was greatly diminished, the riches were stripped from the temples of God and the emperors raised to semi-divine status, and the loss of the overseas grain-exporting provinces to enemy occupation meant starvation for the populace of the magnificent cities of the imperial heartland. 
During the emperor Willibald’s last campaign, poverty and famine brought weakness. Weakness invited plague. It was said that in the capital city of Isenburg a few thousand died daily, and the corpse-piles were as high as the old city walls. By the time of the emperor's demise on the battlefield everyone saw the need for peace. With the Master of Offices von Ladendorf becoming a scapegoat for the monetary policy he pursued on the emperor's behalf and being swiftly executed, his covert work on establishing favourable peace terms was likewise lost, and the peace was harsh for the empire, seeing, for instance, total loss of the western overseas provinces, which, to be fair, more along the lines of acknowledging the actual state of affairs. 
No one, and least of all the new emperor-elect, had foreseen the following rebellion. Atanarich von Steinbrücken, a man from an ancient lineage of minor imperial princes that came to prominence by serving as Counts of the Overseas, was both able and proud. He saw himself as being injured by the terms of the peace and most certainly would not abide by the new reality of him and his descendants being reduced from eminent imperial officials, which his ancestors had been for centuries, to lords of a small and largely insignificant country in the eastern imperial regions. 
As the plague somewhat subsided, Atanarich landed on the western coast with the Army of the Overseas, whose loyalty he still commanded. The defences on the coast were undermanned and poorly maintained, and he easily subjugated a substantial strip of coastline, initially planning on demanding it as a fief and an office. However, he saw the growing discontent of the local nobility, many of which served as army officers by ancient custom, with the old and meek new emperor (who was, speaking plainly, elected specifically because he was thought too meek and old to emulate the centralisation tendencies of his predecessors), and decided to contest the results of the election and sit on the throne himself.
The beginning of the war was auspicious for Atanarich. Though his lack of funds with which to pay the troops compelled him to move quickly, the Praesental army, meant to guard the imperial heartland, through which he was making his way, was decimated by campaigns and plague and thus easily outmatched by his veteran forces. A good number of cities were captured without a single shot being fired as imperial officers withdrew men from the garrisons for fear of malady. 
In the summer of the year 1211 after the founding of the Empire its great capital fell before the enemy for the first time in many centuries. Though the settlement was of great importance and surrendered without offering great resistance, Atanarich, now crowned Emperor, allowed his soldiers to sack the capital, for he could not deliver on his promises of coronation donatives himself. A fire broke out during the looting, and it consumed much of the city, to which poor planning contributed greatly. The ancient Imperial Palace was severely damaged and only saved due to the efforts of Atanarich’s Life Guard, and many great relics of the past vanished in the flame, including the helmet used in imperial coronation ceremonies that, as legend told, the founding emperor Wigbold stripped from the king who reigned these lands and whose name had been consigned to the damnation of oblivion.
However, Atanarich's war was not over: the emperor-elect Theodahad von Waldheim fled to Neu-Egbertsburg and did not accept an offer of peaceful abdication. Atanarich would move to Neu-Egbertsburg at once, but the well-fortified city of Eisenmarkt could not be bypassed, for the force which the emperor-elect's son and Count of the Imperial Retinue Adolf-Gebhard von Waldheim mustered was stationed there, and if Atanarich was to bypass it, Adolf-Gebhard could molest his rear and threaten the cities under his command with impunity. 
Although Atanarich's resources were stretched thin, and he knew that he had to win this war quickly and decisively, he was compelled to muster auxiliary detachments from supportive imperial princes and move on Eisenmarkt, opposed by a motley force of Household and Life Guard and what was left of the Praesental army. 
Failing to capture the city by storm, the pretender was forced to engage in a formal siege. Although in the east his men defended cities much more often than attacked them, the fort artillery was quickly suppressed by Atanarich's own siege batteries, and the parallels of approach were dug at a consistently speedy rate. By the end of 1211, the Army of the Overseas successfully captured one of the redoubts, forcing Adolf-Gebhard to withdraw his troops to the other bank of the river, conceding half of the city. 
That, however, was the last successful action for a considerable time. Despite a new breakout of disease among the defenders and the relentless shelling that reduced most of the fortifications that guarded the islands on the river that flowed freely through the city, Adolf-Gebhard held his bank tenaciously, and even unrest among the citizenry could not sway him to negotiate surrender - he simply turned his guards' muskets and bayonets on the insubordinate people. Adolf-Gebhard's defence held till the summer of 1212, and by that time Atanarich already felt that he did not have nearly enough coin to ensure the continued loyalty of his forces, being dependent on the spoils of war, which were lacking for some time already, and donations from sympathetic princes, which were insufficient. Compelled by the increasingly mutinous sentiments among his unpaid and often poorly supplied troops, Atanarich launched a massive infantry assault across the river, and this paid off - he drove the obstinate prince from most of the city, save for the Household Guard citadel, where Adolf-Gebhard, despite suffering from the malady that ravaged his garrison, led the pitiful remnants of his host. Still refusing capitulation and still a threat, at least by the virtue of displayed ability, he had to be defeated decisively. The Army of the Overseas started looting the city, but was rallied and persuaded to commit to one last push, after which Eisenmarkt would be left to their mercy for two whole weeks. They stormed the citadel, but the prince, despite having to be carried in a sedan chair due to his grave illness, managed to repel them, even though at one point two bastions were in the hands of the pretender's force. 
This defeat broke the willingness of Atanarich's army to campaign further. They looted the once-fabulously rich city clean and compelled their master to abandon the siege with little gain, leaving the hard-won fortificaitons to Adolf-Gebhard and returning to Isenburg with a greatly diminished host. 
Even though the suspicious Theodahad, advised by his court, put his son to death for fear of his ability and suspected ambition, Adolf-Gebhard crippled Atanarich's ability to wage war. Now he did not possess a formidable army anymore, and the imperial princes started deserting his cause. After all, Theodahad had both able generals and a sufficient amount of both men and coin with which to pay them. Less than two years later Atanarich was chased out of Isenburg by the Master of Offices Karl-Sigibert von Kaiserstal and an army he lead in his master's name.
Cornered at the coastline, Atanarich clearly saw that he was defeated. Briefly contemplating suicide and exile, he, reassured by promises of leniency, acquiesced to negotiate with von Kaiserstal. Remarkably, the Master of Offices was, indeed, lenient. Although Atanarich had to abandon his imperial aspirations and pay a large indemnity, he could be useful - and Karl-Sigibert saw that. He proposed a deal: von Steinbrücken would cede his ancestral lands to the imperial control, save for the Steinbrücken castle, but in exchange the emperor would create an office for him and his male descendants to hold - instead of Counts of the Overseas, the von Steinbrücken family would now be Counts of the Imperial Coast, in charge of defending the coast of the emperor's demesne. Additionally, Atanarich would retain control over the very lands he ceded to the emperor - although not as a rightful lord, but as an administrator in the emperor's name. Having no better options in sight, the pretender agreed, thus ending his brief, but certainly devastating war.

Conflict Type

War