1259-1260 : First victories ...
Taking advantage of the weakness of Theodoros, Michael II Doukas, Despot of Epirus, knots an alliance by marring his daughter to William II of Villehardouin, Lord of Achaea, with the posted ambition to take back all the territories conquered by Nicaea under the reigns of Theodoros, John III and Theodoros II.
Informed about the threat, all the more dangerous as Michel has the support of the king of Sicily, Manfred Ier to whom he offered the hand of other one of his daughters, Theodore quickly reacts by making cross the Aegean Sea to his army during autumn 1258, before making it winter in Thessalonica.
Unfortunately once the beautiful days have returned his health is such bad that he canot take part in the operations. It’s Eirene who decides to take the direction of the campaign, a fact almost unthinkable for the period, assisted by the protostator Alexios Doukas Philanthropenos and the general Alexios Strategopoulos. The latter, who has been imprisoned by his father for his failure during the campaign against the fortress of Tzepaina and its sympathies for the Palaiologos party, is so offered an opportunity to redeem itself and rebuild his prestige to the eyes of the crown.
Confiding the regency of the empire to George Muzalon, the young empress so leaves at the beginning of spring Thessalonica with all the Nicaean army, riding the Via Egnatia in the direction of the South of Macedonia. Surprised by the fast advance of the Nicaean army, which take Ohrid and Deavolis without big opposition, Michael is forced to withdrawn up to the Albanian coast, losing many soldiers along the way as well as the major part of his territory.There, he receives reinforcements from his ally Manfred, worried about the military situation but which cannot move personnally. All his attention is indeed retained by the conflict between the Guelphs and the Ghibellines in Central Italy. Thus he sends four hundred german knights to Michael, which are added to the William’s forces, who has entered in campaign at his turn and makes junction with Michael’s army at Berat. In total the allied army. In total, and according to the sources, the allied army is strong about forty thousand to forty-five thousand men (a probably overestimated figure).
From the other side Eirene can only count on an army of about six thousand men, constituted in its great majority by Bulgarian, Cuman, Serbian and Turkish mercenaries. Outnumbered, she decides to avoid direct confrontation, preferring to hold the fortified towns with her heavy infantry and knights and harass the supply train of the enemy army with her light unit, in particular her turkish mounted archers. It’s only at the beginning of September, after several months of skirmishes, that Eirene finally agrees to fight in the region of Pelagonia.
At the same time to these « small war » operations, Eirene makes the bet of playing on the tensions and hatreds between Latins and Greeks. In doing that she gets in touch with John Doukas, lord of Thessaly and illegitimate son of Michael, and makes an offer difficult to decline for him : her hand, and thus the crown of Nicaea in exchange of his support in the battle to come. Although already married to the daughter of the thessalian vlach Taronas John cannot decently refuse the proposal.
He finally makes his decision the day before the battle when a quarrel bursts between him and William II about achaeans knights who have made sexual advances to his wife. Not only William refuses to punish the guilty but in addition insults John by making reference to his illegitimacy. Offended John makes his final decision. Taking pretext of the declarations of a nicaean traitor, who asserts that the Nicaeans are more numerous than the allies believe, he leaves the camp during the night to join Eirene's side.
Michael needs some time to realize to treason of his son. But when it happens he decides, panicked, to flee at his turn the battlefield, leaving William alone and running away as fast as he can in the direction of the west.
In reality Michael has fallen into Eirene’s trap. Indeed the latter, not only counting on John’s desertion, sent a flase deserter to the allies. The result is up to her expectations when the next day William, not informed of Michael’s intentions, discovers that he’s not only facing Eirene’s army, but as well to the Thessalian army.Realizing that he cannot win alone he tries to withdraw but it’s too late for that. Obliged to fight he’s finally defeated and captured by the Nicaeans.
Eirene then obliges him to give her the fortresses of Mistra, Monemvasia and Grand Magne in return of his freedom. Michael on his side finds refuge in Cephalonia, Manfred’s ownership, allowing Strategopoulos to seize his capital Arta and the major part of Epirus.
Unfortunately as Eirene prepares to split her army in order to secure her gains a message reaches her from Nymphaion, announcing the death of the emperor, died in his bath further to an violent epileptic fit.
Now the only ruler of Nicaea, and afraid by an attempt of usurpation of Michael Palaiologos, Eirene has no other choice than to interrupt her campaign to return with her army to Nymphaion. However she decides to leave on-the-spot Strategopoulos, with orders to simply hold the border. Indeed the general hasn’t got enough men, even with the reinforcement of the John’s forces, to hold territories taken to Michael. Who, with the help of Manfred, will meet no difficulty to recover almost all of his Despotate.
But even so the campaign is a complete victory for Nicaea. Indeed the Principality of Achaea, the main and the most dangerous frankish power in Greece, became in the facts an unofficial vassal of Eirene whereas the Despotate of Epirus was rendered powerless by the loss of Thessaly, despite its alliance with the kingdom of Sicily.
... And first treasons
At her return to Thessalonica in mid-october Eirene is horrified to learn that further to the death of her father Michael Palaiologos, pushed by his supporters, took advantage of her absence to murder her regent and proclaim himself emperor of Nicaea. She’s also informed about the refusal of the patriarch Arsenios to crown the usurper andhis exile in a monastery in the island of Proconnesos. As well as support requests made by Palaiologos to the trio managing the Sultanate of Rum, where he had served against Mongols.
But if Izz ad-Dîn Kay Kâwus is favorable to a support of the usurper, it isn't the case of Mu`în al-Dîn Sulayman, vizier of Kay Kâwus's brother, Rukn ad-Dîn Kiliç Arslan, and real master of the Sultanate. Acting behind the scenes, the latter succeeds in convincing Kay Kâwus, who will only offer to Palaiologos a purely symbolic support.
A subtlety which isn’t well perceived by Eirene. Furious, she decides to go without waiting towards Kallipolis where she crosses the Dardanelles, then without losing more time reaches Nicaea which, recognizing her as legitimate empress, opens its doors without fighting. Then she spends winter in the city, taking advantage of this time to establish firmly her authority on Bythinia, Mysia and the nicaean part of Paphlagonia but also to negotiate in secret the price to pay for its forgiveness with the most hesitating allies of palaiologos.
In March Eirene considers herself ready, and walks with her army on Nymphaion, whereas the Palaiologos's mercenary army moves movement to meet her. Both armies meet on March 21st to Adramyttion where they face each other during almost five day. On March 27th, Michel chooses to attack first, uncertain of the loyalty of his partisans. A very bad decision, since he perished in the disaster that ensues. Deprived of their leader, the rebels lay down their arms and implore the imperial forgiveness. Forgiveness which Eirene, in a concern of harmony, grants them. With the exception of the Palaiologos, who are deprived of their titles and possessions and forced to the exile far from Nicaea. Michael’s son, Andronikos, is so going to find refuge in Italy where he’ll start a new life as a trader. As for his family, she’ll need about three hundred and fifty years before finding itself again in a position of power in the Empire.
Now free of any opposition Eirene can emerge as sole leader of Nicaean empire. To this end she published a novella lowering the majority of Nicaean emperors to sixteen, allowing her to rule alone. Then she honores the contract with John Doukas, who meanwhile has repudiated his wife, whom she married on Easter 1260 in Nymphaion.
From this union, that will prove successful, will be born four children : Sophia (1261), Theophano (1263), John (1264) and Anna (1268).
Finally the new empress doesn’t forget the implication of the Seljuks. And although the triumvirate has renewed its desire for peace with Nicaea, everybody knows that Eirene cannot tolerate the threat it poses to her crown.
The Empire of Nicaea (in purple) in April 1260, after the battle of Pelagonia (in orange the Sultanate of Rum and in green the Empire of Trebizond)