[5] His successors could not compensate for this change of focus, and both the Arsenite schism and two civil wars which occurred from 1321–1328 and 1341–1347 undermined further efforts toward territorial consolidation and recovery, draining the empire's strength, economy, and resources.

According to Deno John Geanakoplos, Michael's ancestry could be traced back to all three imperial houses that ruled the empire in the centuries before the Sack of Constantinople in 1204 by the Fourth Crusade.

[6] His mother does not appear to have played a significant role in his early life; at least for a time, he was brought up by his elder sister Martha, the wife of megas domestikos Nikephoros Tarchaneiotes, although she was only ten years older than he.

According to Geanakoplos, "In the period immediately preceding the Nicene reconquest of Constantinople in 1261 no event was of greater importance than Michael Palaeologus' victory at Pelagonia.

"[12][13] This not only neutralized, for the immediate time, the possibility of an attack from enemies on his Western borders, but also improved Michael's legitimacy by showing him as a competent leader.

Rumors of reinforcements for the beleaguered city forced Michael to sign a one-year truce with the Latin Emperor Baldwin II that August.

Genoese help proved to be unneeded when Michael VIII's general Alexios Strategopoulos captured Constantinople from Baldwin II through treachery on 25 July 1261.

According to Akropolites, the public had never really viewed John as emperor - his name was virtually stricken from government business after the death of his father Theodore II, and he had not featured in Michael’s coronation ceremony as co-ruler.

Michael quickly married off John's sisters to two Italians and a Bulgarian noble, so their descendants could not threaten his own children's claim to the imperial succession.

"[19] Michael was aware of the immense influence the Curia had in the West, so he immediately dispatched an embassy to Pope Urban IV consisting of two envoys; upon reaching Italy, the men were seized and one was flayed alive, while the other succeeded in escaping back to friendlier territories.

[21] It was around this time that Michael was presented with a dangerous distraction: ʿIzz ad-Dīn Kaykāwūs, who had been deposed as Sultan of the Seljuk Turks by a coalition led by the Pervane Mu‘in al-Din Suleyman, arrived seeking help from his old friend.

In 1263 Michael sent 15,000 men, including 5,000 Seljuk mercenaries, to Morea with the goal of conquering the Principality of Achaea, but this expedition failed in a surprise rout at Prinitza.

Deserted by even his own officers, who fled to save their own lives, Michael was able to escape by crossing the Ganos Mountains and reaching the Marmora coast, where he happened upon two Latin ships.

Michael secretly negotiated a treaty with the Venetians to grant terms similar to those in the case of Nymphaeum, but Doge Raniero Zeno failed to ratify the agreement.

Michael, as Geanaklopos emphasizes, "from 1266 until shortly before his death in 1282 ... was constrained to devote almost complete attention to the defeat of Charles, the fulfillment of whose ambition would have brought about the destruction of the Byzantine Empire and reimposition of Latin rule in Constantinople.

Geanakoplos quotes Nicephorus Gregoras's comparison of the two men at length: Charles, motivated not by small but great ambitions, implanted in his mind like a seed the resolution of taking Constantinople.

Although the peace treaty with the Seljuk Turks continued to be honored by both parties, nomadic Turkmen had begun to infiltrate the Byzantine territories, and because of Michael's preoccupation with his Western foes, there was no organized response to this threat.

Speros Vryonis also points out that due to his treatment of John IV Laskaris, "there resulted an outright alienation from Constantinople of large segments of Greek society in Bithynia and elsewhere."

Michael returned to negotiating a union of the churches with Pope Clement IV, which he had agreed to, but the latter's death in November 1268 put an end to this approach.

Michael attempted to reason with Patriarch Joseph and the synod of the importance of agreeing to this union, and that the principle of oikonomia (which Geanakoplos suggests is best translated here as "considerations of self-interest") required them to accede to papal demands.

But despite a propaganda campaign over the winter of 1274–1275, Michael was forced to depose Patriarch Joseph and replace him with his own supporter John Bekkos in order to obtain a grudging consent to the union.

[34] Michael VIII achieved an important advantage by this union, for now he gained legitimacy both for possessing Constantinople and for his claims to the lands occupied by Western invaders.

Michael at first responded with comparative leniency, hoping to win the anti-unionists through persuasion, but eventually the virulence of the protests led him to resort to force.

The Arsenite party found widespread support amongst the discontented in the Anatolian provinces, and Michael responded there with similar viciousness: according to Vryonis, "These elements were either removed from the armies or else, alienated, they deserted to the Turks".

Another attempt to clear the encroaching Turkmen from the Meaender valley in 1278 found limited success, but Antioch on the Maeander was irretrievably lost as were Tralles and Nyssa four years later.

John called a final synod at Neopatras in December 1277, where an anti-unionist council of eight bishops, a few abbots, and one hundred monks, again anathematized the Emperor, Patriarch, and Pope.

He tried to take advantage of a civil war in Bulgaria in the late 1270s, but the Byzantine armies suffered several major defeats at the hands of the peasant Emperor Ivaylo.

Donald Nicol lists the Mamluk Sultan of Egypt, who would "loan him ships", and the Tatars of the Golden Horde in South Russia who "could keep an eye on the Bulgarians".

[51] He was denied burial in Constantinople due to his persecution of the Church in support of union with Rome, so was instead laid to rest in a monastery called Nea Mone in the region of Rhaidestos (modern Tekirdağ).

In recovering Constantinople and investing in the defence of his European provinces, Michael VIII began to denude the Anatolian frontier of its troops and was forced to lower their pay or cancel their tax exemptions.