Thanks! Glad you like the TLYou're doing an amazing job !
Thanks! Glad you like the TLYou're doing an amazing job !
Always up for the byzantines surviving!Thanks! Glad you like the TL
They'll definately come in handy in defensive and offensive warfare, both of which the Romans will have plenty of experienceNice victory for the Romans at Achaea, the Romans need to keep those cannons and heavily study them. Adapt gunpowder warfare throughout the entire Empire, it will surely make them a harder target against the Ottomans. Keep up the great work 👍👍👍.
Mehmed dies of a random cannonball to the face, just destroying the Ottoman Empire 🤣🤣🤣They'll definately come in handy in defensive and offensive warfare, both of which the Romans will have plenty of experience
That's the historical fate of Nurhaci Aisingioro lol, Mehmed's fate will be disclosed in another 12 Chapters or so.Mehmed dies of a random cannonball to the face, just destroying the Ottoman Empire 🤣🤣🤣
CHAPTER 10 – A VISITOR IN ITALY
View attachment 898183
- Painting of the pearl of Adriatic, city of Venice, Serene Republic of Venice, circa 1480.
The news of Achaea's swift fall into Roman hands quickly rippled across the Italian peninsula. While many might have anticipated the outcome given the Romans' overwhelming power, they were nonetheless astonished by the speed of their reconquest. The Romans captured Glarentza, a heavily fortified castle, in just about a month, a remarkable feat considering the standards of late-medieval sieges, which could often drag on for months, if not years. People's curiosity was piqued about how the Romans achieved this, and soon, the tale spread through whispers among the surviving Latin defenders.
It transpired that the Romans never intended nor were capable of digging their way through the hard gravel. Instead, they devised a clever ruse. At night, laborers secretly carried dirt and sand from unobserved areas outside Glarentza into the sapping camps under the cover of darkness. During the day, they pretended to dig behind large canvases, only to carry the dirt and sand out of the camps to construct a huge mound. This gave the defenders a false impression of daily progress.
When the mound reached a sufficient height and the morale of the defenders sank to an all-time low, the Romans sent a secret messenger from the seaside to try to persuade a representative of the Giustiniani family. They offered generous terms, appealing to the representative's desire to preserve their trade privileges. The representative, who controlled the port of Glarentza and had numerous connections and influence among the knights and nobles, had no loyalty to Centurione and was eager to maintain their trading privileges. These privileges would be guaranteed and preserved by the Romans if the representative could facilitate a peaceful transfer of Glarentza. Otherwise, they made it clear that no mercy would be shown once the Imperial forces took the castle by force. The trade representative ultimately agreed and fulfilled his part of the bargain.
In June 1417, two crucial meetings discussing the aftermath of Achaea's fall occurred almost simultaneously in Genoa, the nominal benefactor and protector of Achaea, and Venice, the city-state with the most interests and influence in Morea and Achaea. In Genoa, a proposal was brought forward to send a punitive expedition to Morea – the insult against the Serene Republic of Genoa must be repaid with Greek gold or with Greek blood. However, the majority of those present expressed caution, pointing out that Genoa was already embroiled in a long and bloody war against the Duchy of Milan. They had few ships and even fewer men to spare. Given that Achaea had always only nominally been under Genoese control and that Constantinople had agreed to uphold and protect existing Genoese trade interests in the area, most saw military intervention as a waste of valuable resources. An open conflict with the Romans would also pose a great threat to Genovese colony of Galata which were situated next to Constantinople and provided Genoa with vital fund and trade. In the end, Genoa swallowed its pride and signed a formal agreement with Constantinople, acknowledging the change of sovereignty over Achaea.
The Venetians, on the other hand, were far less accommodating. Venice and Rome had extensive diplomatic ties and relations in the past, sometimes cooperative, other times not. In general, Roman-Venetian relations had been relatively cordial over the past five years. The Venetians had successfully dominated the Aegean trade network and sought to protect their holdings rather than expand further. As a result, they saw the severely weakened Constantinople as a potential buffer against the dominant power of the Ottoman Turks, who were still technically at war with Venice following the naval battle of Gallipoli in 1416, although there had been no armed conflicts since the Ottoman navy's crushing defeat. Additionally, the Venetians had gained every possible trade concession from the Romans within Constantinople, to the point where it could be argued that the Romans had fallen under Venetian economic dominance.
When Roman ambassador Nicholas Eudaimonoioannes visited Venice in February 1416, he was warmly welcomed. During his brief stay, Nicholas offered to mediate between the Venetian Republic and the King of Hungary, Sigismund, for the conclusion of peace. He also requested aid in rebuilding the Hexamilion wall that protected the entrance to Morea and urged the formation of a Christian league against the Ottoman Empire. The Venetian Senate gladly accepted the Byzantine proposal to mediate with Sigismund but was hesitant to commit to either of the latter's proposals.
In the year 1417, the Romans' triumphant campaign in Achaea shifted the Venetians' attitude. As the undisputed naval powerhouse in the Aegean Sea, with interests extending deep into Morea and Achaea, the Venetians had long cast covetous eyes on Patras and Glarentza, the two vital trade hubs of Achaea. They had been closely monitoring the Roman campaign, eagerly awaiting an opportunity to seize Patras. However, the swift capture of both Glarentza and Patras by the Romans caught the Venetians off guard, their naval and land forces still unprepared, rendering direct intervention a near impossibility in the short term.
Venice found itself in a predicament. The fall of Glarentza and Patras into Roman hands, along with the potential Roman domination of the Peloponnesus, threatened Venetian interests in the region, a prospect that was unacceptable. Consequently, the Venetian Senate adopted a hardline stance against the Romans, and an official letter was promptly dispatched to Constantinople. Leveraging a lease agreement between Venice and the former Prince of Achaea, Centurione, the Venetians formally demanded that the Romans cede control of Patras to Venice and restore Centurione to Glarentza and several other castles and holdings. This was aimed at restoring a balance of power and checking Roman expansion.
The Romans took the Venetian demand seriously. Accepting the Venetians' terms would be humiliating and would undermine their hard-earned gains. However, the Empire was not in a position to risk a potential open conflict with Venice. A delicate diplomatic balance needed to be struck. On the 6th of July, a Roman delegation of a dozen men, led by Andronikos, Despot of Thessaloniki, and Plethon, a renowned Roman philosopher in Italy, arrived in Venice to negotiate terms. The Venetians greeted them with a polite but cold reception, a stark contrast to the warmth shown to the previous Roman diplomatic mission.
Before the official meeting, Andronikos took a brief tour of the city, fascinated by Venice's industrial might, particularly the immense Arsenal complex, where galleys and firearms were produced in vast quantities monthly. After several days of waiting, the Roman delegation was finally granted a meeting with Doge Tommaso Mocenigo, a war veteran of the failed Nikopolis Crusade in 1396. Initially, the Doge adopted a strong and arrogant stance, refusing to entertain any modifications to their demands and insisting that the Romans accept all terms unconditionally.
The Roman delegation, however, displayed humility yet firmness, remaining patient and refusing to yield under Venetian pressure. The initial meetings ended with no progress for either side. As time wore on, the Venetians' impatience grew, their tone becoming increasingly harsh, culminating in veiled threats of war.
However, the Venetians' true intentions began to emerge. Aware that their truce with Sigismund, emperor of the Holy Roman Empire, was set to expire in April of the following year, and noting the significant rise in the prices of wheat, leather, iron, and other war materials in Venice, Andronikos and Plethon deduced that the Venetians were amassing provisions for a potential war against Sigismund. In such a scenario, Venice could not afford a prolonged conflict in the Aegean, given the threat posed by Sigismund's might in Dalmatia. Sigismund, with the potential to mobilize tens of thousands of men from Hungary, Croatia, and the German states, posed an existential threat to Venice, far greater than the annoyance posed by the Romans.
As autumn approached and the Venetians' bluster failed to achieve its desired effect, their position began to soften. After several rounds of negotiations, on August 14th, 1417, an agreement was finally reached. The Romans would retain Glarentza and "redeem" Patras from Venetian lease, paying an upfront fee of 2,000 ducats and an annual fee of 300 ducats for ten years. Additionally, the Venetian navy and trade fleet would be granted free access to the port of Patras for fifteen years, and Venetian merchants in Patras would enjoy tax exemption for the same duration.
The signing of this agreement marked the conclusion of a successful Roman campaign. However, Andronikos and Plethon did not return home. Instead, they traveled north across the Alps towards the German Archbishopric of Konstanz, where they were invited by Emperor Sigismund to participate in the final stage of the Council of Konstanz. Their mission was to help elect a new pope and resolve the Western Schism, while also discussing the prospect of a Crusade.
[1] The Venetians intervened OTL and gave such terms to Constantinople, which the Romans reluctantly agreed – prolonging the rule of Centurione in a few Latin holdings in Achaea for another decade.
[2] From 1412 to 1423, Emperor Sigismund campaigned intermittently against the Republic of Venice in Italy with the aims of taking the rich Dalmatian cities and cut down Venetian influence in the area. The Venetians on the other hand planned several assassinations attempts on the emperor.
Thanks for the input, always appreciative to suggestions Before participating the Lombard Wars, Sigismund had in fact already traded blows and went to war with the Venetians, namely in Dalmatia. As king of Hungary, Sigismund thought Dalmatia as a natural part of his Croatian holdings, and saw the Venetian activity in the area an infringement and threat. Fighting and sieges occurred sporadically from 1406 to 1413 (if I recall correctly), neither side could achieve victory, and in the end they called a essential white peaceReally well written chapter, especially the part where Andronikos visits the Serenissima (did he take some inspiration from it?) and then travels to Constance at the invitation of Sigismund to participate in the council to put an end to the Western schism, I only have to make a clarification, namely the conflict between Sigismund and Venice, which was part of the wider Lombard wars ( 1423 - 1454 ) and which began as an imperial response to Venetian expansionism on the Italian mainland ( which also involved the patriarchate of Aquileia and other local cities, which were eventually annexed by the Venetians, Aquileia in particular being an important state in the HRE apartment in Italy, had required the direct intervention of the Emperor )
CHAPTER 11 – SUPER GRAMMATICAM
Sigismund of Luxembourg was elected King of Germany (King of the Romans) in 1410, as well as prince-elector of Brandenburg (1378–1388 and 1411–1415). He was the last male member of the prominent House of Luxembourg.
Sigismund was the son of Charles IV, Holy Roman Emperor and his fourth wife Elizabeth of Pomerania. He married Mary, Queen of Hungary in 1385 and was crowned King of Hungary soon after. He fought to restore and maintain authority to the throne. Mary died in 1395, leaving Sigismund the sole ruler of Hungary.
In 1396, Sigismund led the Crusade of Nicopolis, but was decisively defeated by the Ottoman Sulatan Bayezid Thunderbolt. Afterwards, he founded the Order of the Dragon to fight the Turks and secured the thrones of Croatia, Germany and Bohemia. Sigismund was one of the driving forces behind the Council of Konstanz (1414–1418) that ended the Papal Schism, but which also led to the Hussite Wars that dominated the later period of his life. He would later be crowned Holy Roman Emperor and ruled until his death.
Known for his regal attitude, when at one point during the council of Konstanz a cardinal corrected Sigismund's Latin, Sigismund replied Ego sum rex Romanus et super grammaticam ("I am king of the Romans and above grammar")
- A portrait of Emperor Sigismund, painted after the emperor's death.
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When Plethon and Andronikos arrived at Konstanz on 5th October, they were greeted by the Roman diplomat Nicholas Eudaimonoioannes, who had been participating the Council of Konstanz on the Empire’s behalf for a year. Plethon and Nicholas was old acquaintances and colleagues from Morea. After a brief rest from the long journey, Nicholas gave an update of the current situation to Plethon and Andronikos, and the reason why he invited them to Konstanz soon becomes clear.
The council of Konstanz had been ongoing for almost three years. Originally, the main purpose of the council was to end the triple Papal schism which had resulted from the confusion following the Avignon Papacy. Pope Gregory XI's return to Rome in 1377, followed by his death (in 1378) and the controversial election of his successor, Pope Urban VI, resulted in the defection of a number of cardinals and the election of a rival pope based at Avignon in 1378. After thirty years of schism, the rival courts convened the Council of Pisa seeking to resolve the situation by deposing the two claimant popes and electing a new one. Though the elected Antipope Alexander V and his successor, Antipope John XXIII, gained widespread support, especially at the cost of the Avignon antipope, the schism remained, now involving not two but three claimants: Gregory XII at Rome, Benedict XIII at Avignon, and John XXIII. Therefore, many voices, including Sigismund, King of the Romans and of Hungary (and later Holy Roman Emperor), pressed for another council to resolve the issue. That council was called by John XXIII on 16 November 1414 in Konstanz.
With the support of Emperor Sigismund, the Council of Konstanz recommended that all three papal claimants abdicate, and that another be chosen. Gregory XII then sent representatives to Konstanz, whom he granted full powers to summon, open, and preside over an Ecumenical Council; he also empowered them to present his resignation of the papacy. This would pave the way for the end of the Western Schism.
On 4 July 1415 the Bull of Gregory XII was formally read before the assembled bishops. Prince Malatesta then informed the council that he was empowered by a commission from Pope Gregory XII to resign the Papal Throne on the Pontiff's behalf. The bishops voted to receive the Papal abdication immediately. Thereupon the commission by Gregory XII authorizing his proxy to resign the Papacy on his behalf was read and Malatesta, acting in the name of Gregory XII, pronounced the resignation of the papacy by Gregory XII and handed a written copy of the resignation to the assembly. Followingly, the other anti-popes were all deposed. Gregory XII's cardinals were accepted as true cardinals by the council, but the members of the council delayed electing a new pope for fear that a new pope would restrict further discussion of pressing issues in the church.
However, before the new pope was elected, another controversial matter was brought before the council - the heresy of Jan Hus. Initially summoned to Konstanz under a letter of safe conduct, after several theological debates where Jan Hus and his followers stood firm against accusations from conservative bishops, he was later found guilty of heresy and turned over to the secular court, which on 6th July 1415 sentenced him to be burned to death at the stake. This act was seen as an outrageous betrayal by Hussite followers, and seeds of discontent and rebellion begin to spread throughout Bohemia.
When Nicholas arrived at late March 1416, the Council was at its critical stage of electing the next Pope. Many names were put forward, each with backing from prominent figures such as established Italian noble houses, influential cardinals, the Monarchs of Europe such as King of France or Emperor Sigismund of the Holy Roman Empire. Nicholas was well-known for his natural gift to socialize, always able to read the room and say the words most pleasant to the ears of the listener. As soon as he arrived, he managed to identify the deciding figure in the Papal election, Emperor Sigismund and focus on befriending the emperor who himself was also a gregarious man. As both men were interested in a united Catholic Church to sponsor a renewed crusade, the two soon formed a close friendship and working relationship, where Nicholas helped Sigismund to persuade people of importance to the election behind the scenes. It was with Nicholas’ assistance that the candidate favored by Sigismund, the 48 years old clergy man Otto Colonna became the man favored by most electors and most likely to become the next Pope.
Bringing the Western Schism to a successful end was no small feat which required enormous amounts of efforts and diplomatic skill – the result will inevitably provide Sigismund with significant prestige and authority throughout Catholic world. With strengthened position at home and a Pope of his backing, Sigismund could now focus his energy on planning for the next crusade against the Ottomans, of which Constantinople could potentially play a very critical role. The recent Roman success in Achaea no doubt improved its standing in Sigismund’s eyes, so when Nicholas asked him for an audience with the newly arrived Roman delegation nominally led by son of Emperor Manuel II, Despot of Thessaloniki Andronikos, he happily agreed.
As for why Nicholas would need to bring Andronikos all the way from Venice to meet Sigismund, was due to one simple fact – the ever-cautious Emperor Manuel II though had given Nicholas the authority to initiate a discussion of fermenting a crusade, had refused to give any concrete promises on Roman participation in such crusade. To Nicholas, he fully understood his emperor’s position – the crusade was far away and distant in the future with many uncertainties, while the Ottomans was close by within vicinity and had every means to utterly devastate the Empire. There were inherently no wrongs in be cautious and not anger the Ottomans before circumstances become clear. That being said, Nicholas knew well the ever-pragmatic Sigismund would need to be assured of Roman involvement, before crusade goes into any meaningful preparations, therein lies the dilemma - to help organize a crusade that have the potential of decisively destroy the Ottoman threat to the Empire once and for all, Nicholas must disobey the explicit order of his Emperor. For that to happen, and to make his case convincing to Sigismund, Nicholas would need someone with more credibility, who better than a son of Manuel II, Despot of Thessaloniki? As soon as he heard of Andronikos’ arrival in Venice, Nicholas knew his only chance to convince Sigismund and set the crusade in motion had arrived.
Nicholas had initially expected a long and difficult effort to persuade the young Despot to consciously disobey his father. To his surprise Andronikos was surprisingly accommodative to his idea. Nicholas soon realized that Andronikos shares his view on the Ottoman threat. Opposed to the risk-adverse strategy of constraint adopted by Manuel II, Andronikos was far more risk-taking and view the Ottomans as the foremost existential threat of the Empire and therefore must be weakened at every opportunity – and the only opportunity to destroy Ottoman threat once and for all was through a crusade. Dire situation calls for radical measures, and Nicholas, Andronikos and Plethon were all willing to take the risk to give the Empire a chance to rise. Determined and ready to bear any responsibilities, it was on 16th October that the meeting between Sigismund, Andronikos and Nicholas happened.
The failure of the last crusade of Nikopolis in 1396, of which Sigismund was the leader, had always lingered at the back of his mind. It reminds him that the sole effort of his powerbase in Hungary and the nearby allies of Serbia, Bosnia and Wallachia were not enough to overcome the Ottoman threat.
Despite being significantly weakened by the Timur invasion and the subsequent civil war, the Ottomans retained a firm grip over the Balkan territories, possessing a formidable army and a vast pool of manpower. Sigismund was convinced that to succeed, he must unite all forces under a single banner of crusade. With this objective, he founded the Order of the Dragon in 1408, a military order modeled after the Crusades, calling upon its members to defend the cross and wage war against the enemies of Christianity, primarily the Ottomans.
Sigismund held high hopes for the Romans' participation in the crusade. Their geographical position could serve as a strategic asset, hindering Ottoman reinforcements from Asia. The meeting with Andronikos proved fruitful as they shared a common goal. Sigismund was elated to find a kindred spirit in Andronikos and offered to spearhead a crusade that would unite the Christian world, vanquish the Turks, and restore vast territories to the Roman Empire.
Andronikos promised Sigismund that once the crusade was ready, the Empire would stand beside them. However, he cautioned that joining the crusade prematurely could alert the Turks and rob them of the element of surprise. Sigismund acquiesced to this wisdom.
After countless hours of intense debate and deliberation, Sigismund, with steely resolve, vowed that upon the election of the successor to the papal throne and the reunification of the Catholic world, he would persuade the new pope to issue a passagium generale, effectively declaring a crusade against the Ottoman Empire. This call to arms would resonate throughout the Order of the Dragon, an esteemed assembly encompassing monarchs and nobles from Hungary, Serbia, Croatia, Bosnia, and Wallachia. Moreover, contingents from Poland and Bohemia had vowed to join this grand crusading army, while Venice had in secret already pledged to the Pope its naval support in an upcoming Crusade, and Italian city-states and the Papal State would surely commit to providing financial aid.
Sigismund's projections indicated that in three years, by the turn of 1419 into 1420, a formidable crusade army numbering approximately 30,000 men would be poised to strike the Ottomans. At that juncture, the Romans, in tandem with the Venetian fleet, would be tasked with sealing the Dardanelles Strait, while harassing the Ottoman rear through their strategic positions in Constantinople and Thessaloniki. This would create the ideal conditions for a decisive victory, one that would once and for all evict the Ottomans from Christian lands.
With the crusade now in motion, Nicholas, Plethon, and Andronikos participated in the final vote that elected Otto Colonna as Pope Martin V. The wise Master Plethon even engaged in an engaging intellectual discussion with the new pope, who expressed keen interest in Plethon's profound knowledge of Greek philosophers from the Classical Age.
As November progressed, Nicholas remained in Konstanz to oversee the conclusion of the Council, while Plethon and Andronikos departed for Italy. Embarking on a ship, they sailed across the Adriatic Sea, heading towards the Aegean. Weeks later, Plethon disembarked in the newly revitalized harbor of Patras, bidding farewell to his young friend before resuming his duties as magistrate of Morea. However, before Andronikos could return to his home in Thessaloniki, he was obliged to sail around the Peloponnese towards Constantinople, where he was duty-bound to report the outcomes of his journey to his father, Emperor Manuel.
At the serene palace of Blachernae, the aging emperor Manuel initially greeted the news of Andronikos's diplomatic success with the Venetians with a approving nod. His face, creased with years of wisdom and power, broke into a rare smile as he heard of the agreements reached.
But that smile vanished as quickly as it had appeared when Andronikos mentioned his clandestine meeting with Sigismund. Manuel's expression shifted from one of mild interest to one of stark disapproval, his brows furrowing in a deep scowl.
Andronikos, well aware of the potential backlash, had been cautious not to promise anything concrete before a crusade was firmly in the planning stages. Nevertheless, he had underestimated the fury of his father, whose anger burned hotter than any fire. Manuel was enraged that his son had dared to negotiate with a foreign monarch without his permission or authorization, potentially jeopardizing the delicate balance of power with the Ottomans.
A furious scolding erupted in the palace, a rare display of emotion from the usually composed emperor. Manuel's voice rose to a near-shout, his hands gesturing angrily as he berated his son. The peace with the Ottomans was precious and hard-earned, he shouted, and Andronikos's foolishness could shatter it all.
To Manuel, the Ottomans were a constant threat, and he had walked a careful line with Sultan Mehmed, extracting concessions while avoiding any provocations that could tip the balance in their favor. If Mehmed learned of an alliance between Constantinople and Sigismund, and of Roman involvement in a crusade, it could spark a catastrophe. The Ottomans might unleash their full wrath upon the Empire, and Manuel would be left with no allies to turn to, as the Crusade, even if were up to their words, would need another three years to be ready – the Empire could very well have perished by then.
Moreover, Manuel had been secretly plotting to meddle in Ottoman succession or other internal struggles once the Sultan's health began to fail. He needed the Ottoman court to remain friendly or neutral, and Andronikos's folly had threatened to destroy all his carefully laid plans.
Now, because of his son's recklessness, Manuel's plans were in jeopardy. Sultan Mehmed, alerted by Roman involvement in Konstanz, would never again willingly put his princes into Roman custody as had been the norm in the past. This denied Manuel a key bargaining chip in any potential Ottoman succession crisis.
And an angered and suspicious Sultan Mehmed might well turn his full attention to the Romans, curtailing their breathing room and potentially leading to a deep crisis where the Ottomans focused all their efforts on conquering Roman lands and destroying the Empire once and for all.
As the firestorm he had unwittingly created continued to rage, Andronikos found himself alone and exposed. But in the midst of the crisis, his elder brother and co-emperor Ioannes came to his rescue. A secret participant in the Roman deal with Sigismund and a co-conspirator with Andronikos, Ioannes managed to drag his brother away from the scene and returned to calm their father down.
Unlike their father, Ioannes saw the Ottomans as the greatest existential threat to the Empire, and he believed that a crusade was the only way to eliminate them once and for all. Therefore, he was willing to facilitate a crusade even if it risked Ottoman retribution or defiance of their father.
Manuel, noticing his sons' attitude, realized that he was the minority in his own court. His hawkish sons had already made up their minds to take a risky step further, and there was nothing he could do to stop them. With a heavy heart, he reluctantly acknowledged the situation on the ground, while praying fervently that the aggressive attitude of his sons would not lead the Empire down a spiral path to destruction.
As of now, except the butterfly effect of Andronikos and the declined health of Mehmed, other political calculations had mostly stayed the same as OTL. As the TL progress and the effect of the butterfly becomes more impactful, the political landscape of Europe and Asia will indeed be affected - a Chapter delving into the aftermath of Andronikos' butterfly effect will be written, there's still some Chapters to go before we reach to that point. That being said, Sigismund has been known as a larger than life and a grandiose man. It is quie likely he spoke of 'possibilities' but gave the impression of 'certainties', so it is wise to not trust every words he says - a fact the inexperienced Andronikos failed to grasp, the experienced diplomat Nicholas in his fervent pursuit for a crusade chose to ignore, and what made Manuel so angry was his son falling prey to the lofty promise and risk endagering the Empire with his recklessness.Ooh so we finally have the election of Otl Martin V ( so I imagine that Henry V used as Otl, his right of veto in the conclave, obtained as thanks from the new pontiff, for the help given to him in his election, now it remains to understand if England manages to maintain this privilege in the future ) the part regarding the preparations for the crusade is very interesting ( even if I think that Sigy has perhaps promised a little too much, compared to what he can actually put in place ( especially with the problem of the Hussites, who immediately occupied an important part of his resources in Otl, so if he wants to keep his word, he must find a temporary way to weaken them, just enough to concentrate on the crusade ) also also manage to finally be crowned Emperor in Rome, it could allow him to use / call up more resources ( although I think his coronation ceremony would be more impactful after a successful crusade ) the interest of the Italian states in the enterprise is also very interesting ( which can only increase the chances of success, perhaps England and Aragon might also be interested in helping out, even just by sending small groups of soldiers, in addition obviously to the Crusader Orders ) otherwise I think with better future collaboration between Sigismund and Andronikos, can favor an easier solution to the problem of the meeting of the churches than Otl ( especially after a possible successful military campaign against the Ottomans ) small side question, would it not be the case that Manuel, after learning of the " madness " made by his unwary sons, ask for the strengthening / expansion works of the Theodosian walls as a precaution
As of now, except the butterfly effect of Andronikos and the declined health of Mehmed, other political calculations had mostly stayed the same as OTL. As the TL progress and the effect of the butterfly becomes more impactful, the political landscape of Europe and Asia will indeed be affected - a Chapter delving into the aftermath of Andronikos' butterfly effect will be written, there's still some Chapters to go before we reach to that point. That being said, Sigismund has been known as a larger than life and a grandiose man. It is quie likely he spoke of 'possibilities' but gave the impression of 'certainties', so it is wise to not trust every words he says - a fact the inexperienced Andronikos failed to grasp, the experienced diplomat Nicholas in his fervent pursuit for a crusade chose to ignore, and what made Manuel so angry was his son falling prey to the lofty promise and risk endagering the Empire with his recklessness.
As for the Theodosian walls, it has always been on the mind of Manuel, since it was that wall which saved him and Constantinople from a 5 year long siege of Bayezid Thunderbolt. He has put most of his fund into repairing the fortifications.
Certainly, Sigismund spent his life fighting one fire, and another one, then another one. None of his vast domain provided him comfort, (perhaps except Brandenburg) it was almost like an endless journey of whack-a-mole, solving one difficult problem before another one pops up.Well I can understand that Manuel might rightly believe Andronikos to have been too naive, but in Sigismund's defense, his dynastic legacy ( which was something not seen by the imperial princes for at least a good 2 centuries, was a little scary, because they feared what he could do with the unified resources at his disposal of Bohemia, Hungary, the Luxembourg dominions remaining in the west, plus the role of Emperor ) also the fact that he had taken over after the disasters of the governments of Robert and Wenceslas and in the midst of the schism of West, did not make his task any easier ( to which is added the increasingly present Ottoman threat ) so it is normal that he could not concentrate on a single front at a time, as he actually wanted to do ( in this he is very similar to Charles V, except that he at least could count on his family's loyalty, which Sigy couldn't do, as half of the troubles he faced were caused by his relatives' past actions, and at most he could certainly only count on Albert II of Habsburg )