@NotAMyth thank you kindly!
@Oda see below.
Through the rugged Morea, the Emperor of the Romans and his one-hundred man escort marched, untroubled, uninterrupted; a column of mailed horsemen, the Palaiologos' twin-headed eagle once again fluttering above their helmeted heads.
Though he was but a boy -- none would ever accuse Antigonos of being a
child -- Antigonos was, clearly to all who saw him, the master of this expedition; so determined and proud was his bearing. And it was now, on this journey south to Mystras, that the Emperor's troops truly began to love him. Everywhere he went, men saw the ghost of his soldierly father in Antigonos -- in his rough mannerisms, in the way that he would enjoy no comfort that his soldiers could not share, in how he would sing his warriors' ribald marching-songs.
On and on, they rode; slow, deliberately slow, their mail rustling, leather creaking, horses snorting and sighing. The Emperor slept beneath the stars, surrounded by his faithful retinue, always with a blade besides him. He visited small villages and offered their inhabitants whatever gifts he could spare -- rings, pieces of gold, precious gems -- sharing the poor villagers' figs and fermented milk, but always careful to not outstay their welcome or take too much.
Demetrios, holed up within Mystras, must surely have dreaded the arrival of his young nephew. He had been recalcitrant and, indeed, treacherous. Ambassadors from the court of his brother's killer, Mehmed, had enjoyed the Despot's hospitality. It would seem that Demetrios' dreams of becoming the Emperor of the Romans -- indeed, even as the catspaw of the Ottoman Sultan -- had never strayed far from his mind.
And yet, what did Demetrios have to worry about? His garrison numbered some nine hundred men; hidden within Mystras' sturdy walls, fierce men all. Not only that, he was also more than twenty years the Emperor's senior; a veteran of conflict, a man whose lips had been wetted by the blood of the Turk -- Turks who he now courted, avariciously.
If --
when -- the young Emperor arrived in Mystras, Demetrios would make his nephew submit and recognise him, as the senior Palaiologos still alive, as the true Emperor of the Romans.
Or so he thought.
A fortnight after their quiet departure from Patras, Antigonos and his escort arrived at the gates of Mystras. The gates, old wood banded with iron and carved to display the House of Palaiologos' eagle, remained barred.
The soldiers of the Emperor's retinue grumbled amongst themselves and grew weary. It was a cold midwinter day, the sun pale and watery, with a biting wind and the threat of rain upon the skies. Only after some time did the gates open and Antigonos led his men within the walled city, riding with long-haired Rhangabes at his side.
His uncle Demetrios awaited within the Palace. Here, the Despot greeted his nephew formally and coolly, offering his condolences to Antigonos about the loss of his father, mother and, perhaps most importantly to the greedy man, Constantinople. Then, in a moment of brilliance, he charmed Antigonos with his daughter, Helena. Helena was a few months older than Antigonos, as pretty as she was bold, high-spirited, her father's flower.
Demetrios had, in his efforts to woo the Sultan, offered Helena's hand to Mehmed. Now he watched -- perhaps infuriated, perhaps ashamed of his plotting -- as Helena and Antigonos became firm friends; sharing smiles and laughs, Antigonos regaling his cousin with tales of Constantinople and Naxos and his father, all under the careful eye of Rhangabes.
That night, at a grand feast thrown in the Emperor's honour, discussion turned to matters of importance. Antigonos lanced his uncle with questions. He inquired, with increasing pressure, why Demetrios had not come to swear fealty to him in Patras. Demetrios no doubt weaseled his way out of the predicament, because the next morning the two enjoyed a boar-hunt together in the forests surrounding Mystras.
For three weeks, Antigonos enjoyed the comforts of Mystras; hunting with his uncle, remembering his father in solemn fireside stories and spending great deals of time with Helena.
On the fourth week, an ambassador from the Sultan arrived almost unnoticed in Mystras. Mehmed's terms were clear: seize Antigonos and Mehmed would see that Demetrios was crowned in his place.
The Despot had, however, grown fond of his nephew and hesitated. Word of Demetrios' duplicitous nature somehow reached the young Emperor and he acted at once.
As Demetrios said his morning prayers, Rhangabes and a dozen of the Emperor's retinue seized him and clamped him in chains. Helena and Demetrios' wife, a member of the prestigious Asen family named Theodora, were also locked away. Antigonos, now enthroned in Mystras, summoned the garrison commanders to his side and presented them with evidence of Demetrios' treachery. Those found complicit were executed. Most, ignorant of their master's true nature, knelt and swore themselves to Antigonos.
Antigonos showed his uncle mercy. He spared Demetrios' life, but had the man blinded and castrated and confined to a life in a monastery. No longer would he plague the young Emperor. Theodora, Demetrios' wife, was given a charitable appanage and permitted to remain in Mystras.
Helena, despite her father's mutilation and imprisonment, did not suffer any consequences. Indeed, in the Emperor's court, she flourished; a favourite of her cousin, a constant companion until her marriage, and if the rumours were true, his first love -- although Antigonos would himself deny such a notion.
Demetrios languished for another three years before his death. Some tales -- unproven but popular -- suggest that Demetrios was killed on orders of the young Emperor. One account, particularly fanciful, names Rhangabes himself as the killer.
The Turkish ambassador, imprisoned during Antigonos' seizure of Mystras, was allowed to leave unharmed on account that he bore a message to the Sultan on behalf of the Emperor.
It read, in Antigonos' typical laconic manner:
'Stay away.'