In the winter of 1466, the war between Austria and Venice continued.
Austria, Genoa, and Naples united to engage in increasingly fierce pirate battles with Venice across the vast sea from the Adriatic Sea to the Eastern Mediterranean.
However, the Gulf of Venice, which should have been the most dangerous, was unexpectedly calm.
The Habsburg fleet was stationed in Trieste, while the Venetian Adriatic Sea fleet was stationed in Venice, with both sides sending out several warships daily for reconnaissance and skirmishes.
These continuous small-scale naval battles mostly ended in Venetian victories, but the Austrian warships were fast enough and did not suffer many losses.
Dujam strictly followed Laszlo's orders, avoiding battle, which made the Venetian, who were eager to defeat the Austrian navy and return to the Aegean Sea, incredibly anxious.
They had sent out their entire fleet multiple times to blockade the port of Trieste, but no matter how much the Venetian provoked, the Austrian fleet simply would not come out.
One Venetian warship even got too close to the port and was hit by cannons from the temporarily constructed shore defense batteries; although it did not cause much damage, it was enough to make the Venetian dare not approach the port easily again.
In other sea areas, ships from both factions attacked and plundered each other, turning the entire Mediterranean Sea into a chaotic mess.
In some villages along the Dalmatia coast, entire communities abandoned farming their barren land, taking old oar-powered sailboats to sea to find suitable prey.
Both Venetian and Austrian merchant ships were their targets. Initially, Laszlo had not noticed, until a group of pirates was defeated and captured by the Frankopan Family's fleet, and he was startled to realize that the Dalmatia pirates had resurfaced.
Subsequently, the Kingdom of Hungary's Split Army, with the help of the Frankopan Family, swept through several pirate lairs disguised as fishing villages along the coast, finally making these unruly pirates restrain themselves considerably.
The negative impact of privateering laws went far beyond this; more and more pirates emerged, providing services to both Austria and Venice, attacking enemy merchant ships and even warships.
This dealt a heavy blow to Austria's nascent maritime trade, but at the same time, it caused the Venetian to continuously suffer significant losses.
The scope of this great war was unprecedented; due to the war, the prices of some important commodities within the Empire fluctuated wildly, leading countless merchants to the brink of bankruptcy.
Even worse off were the people of the Balkans, as the most brutal land war erupted there.
Bulgaria and the Serbian Army rapidly invaded Greece, where they successively captured several Venetian trade outposts and fortresses.
Wherever they passed, all valuables were plundered.
Ordinary people often had to surrender all their possessions to gain freedom; those who could not pay were relegated to slavery.
Some were taken in by the Teutonic Order, while others were left to the disposal of their captors.
Anyway, those living there were either Orthodox Christians or Venetian. For the Bulgarian-Serbian Allied Army, whose main force consisted of Crusade lords, these people were also part of their spoils of war.
Especially the lords of Bulgaria, their demand for population had reached an exaggerated level.
It is important to know that ever since the Ottomans destroyed the Second Bulgarian Empire, this land had successively experienced the Ottomans Civil War, the Sheikh Bedreddin Rebellion, and the Crusade, leading to continuous and severe damage to Bulgaria's population.
As the saying goes, "where soldiers pass, nothing remains; where bandits pass, even the comb is left bare." The harm caused by war requires long-term stable rule to recover.
Originally, as Laszlo's conquest of the Balkans gradually completed, Bulgaria's geopolitical environment also stabilized. The sparsely populated land, suitable for livestock development, attracted a large number of immigrants from other parts of the Balkans, as well as from farther Hungary and the Empire.
Accompanying this wave of immigration from the west, many missionaries and bishops from Rome, with the help of the Order of Saint George, began to establish roots in the Bulgarian countryside.
They built churches and monasteries, even forcibly seizing Orthodox Church monasteries, compelling the populace to perform Western Church rituals in churches, or to pay more taxes.
In areas with few German and Hungarian immigrants, Orthodox Christians sometimes chose to resist the invasion of the Roman Catholic Church with force. They had thrown missionaries into rivers to drown them, or put people in sacks and abandoned them in the wilderness to fend for themselves.
These terrifying methods, without exception, were met with even bloodier retaliation from the Teutonic Order.
Hatred continuously accumulated during this process, but the local feudal lords of Bulgaria were the first to submit to the Emperor. To preserve their power, they took the lead in converting to Roman Catholicism and began promoting Western religious beliefs in their respective territories.
This led to a gradual intensification of conflicts between the ruling class of Bulgaria and the common people at the bottom.
It was in this high-pressure environment that the Ottomans began to secretly infiltrate the lower-class Bulgarian populace.
Of course, it would not be Muslims who helped the Sultan constantly incite Bulgarian rebellions; this work was carried out by the Greek.
After the fall of Constantinople, those Eastern Roman Empire survivors who were unwilling to accept infidel rule tried every means to escape to the West.
They brought the culture, art, and other Essence of the Eastern Roman Empire to Italy, Hungary, and Austria.
Those Eastern Roman or Greek people who hated the Western Church remained in Constantinople and were resettled by the Sultan.
They prided themselves as true descendants of Roman Greece and supported the Sultan's cause to conquer those Western barbarians and Slavic savages, hoping to gain higher status through this.
A prominent representative among them was Patriarch Gennadius II, who generously contributed for the position of Patriarch of Constantinople.
He followed the retreating Dimitrios from Morea to Constantinople and quickly gained the appreciation of Mehmed II.
A group of Orthodox believers who most detested the Roman Church quickly gathered around him. Upon receiving the task from the Sultan, they immediately set off for the vast rural areas of eastern Bulgaria.
Although the influence of the Roman Church had reached this area, it had been slow to take root.
Most Western missionaries, for their own safety, chose to center their activities around Sofia, the capital of Bulgaria, safely spreading their faith under the protection of the Teutonic Order.
Only those who were not afraid of death, or who had received enthusiastic invitations from Eastern lords, would then go to the East to spread their faith.
It was this situation that provided an opportunity for the Ottomans.
"Now the Sultan is the protector of the Orthodox; those German will only persecute you. Are you going to endure it forever?"
In a small church in the mountains near Great Tarnovo, the capital of the Tarnovo Principality, a Greek missionary from Constantinople shouted to the villagers who had repeatedly listened to his sermons.
"But those iron cans are ruthless killers who cut down resistors as easily as cutting down scarecrows."
Such a voice came from the crowd, full of fear of the Order of Saint George.
There was even a branch of the Teutonic Order within Great Tarnovo itself; they had previously punished those Bulgarian who had committed evil deeds against Roman missionaries.
"You are not the only ones suffering their oppression; many more Orthodox believers have been persecuted, and they will join you in resistance."
The villagers did not know if the Greek priest's words were true, but seeing his confident demeanor, most chose to believe him.
"Of course, we are unwilling to accept the rule of heretics; they force us to pay more taxes.
But will the Ottoman Sultan you speak of truly treat us kindly?
Many here have experienced the Ottomans rule of over fifty years before, and that was not a pleasant memory."
The village elder, standing at the forefront, interrupted the Greek's highly inflammatory speech with a stern face.
Although he was equally dissatisfied with the German rule, this Greek clearly wanted to trick them into their deaths with empty words, and he would not stand by and let it happen.
"No, no, the Sultan merely welcomes you to settle in Constantinople, the most inclusive metropolis in the world.
Of course, if your resistance ultimately succeeds, you can continue to live freely on this land.
Right here in Great Tarnovo, we also have companions. They have found descendants of the last Tsar Ivan Shishman and hope to enthrone him as the ruler of Bulgaria, replacing that Austrian who has not come to Bulgaria for many years, and rebuild the Bulgarian nation.
The Sultan promises to provide help to the Bulgarian who bravely resist the Roman Emperor."
Seeing that the villagers were not easily swayed, the Greek priest threw out a bombshell.
As soon as these words were spoken, the previously quiet church immediately became noisy, and people began to dream of the scene the Greek described.
Descendants of the Shishman family leading them to overthrow the Emperor's rule, rebuild the Bulgarian Empire, and expel those heretics from the West.
"Now the Bulgarian Army is fighting the Venetian in Greece. Those heretics are killing each other, which is a great opportunity for you to break free from your shackles; you must not miss it."
How could the Bulgarian commoners, who had been cooped up in the mountains, know how powerful the Emperor truly was?
They only heard that Bulgarian forces were stretched thin, and they cast all their worries aside, beginning to dream of rebuilding the Bulgarian Empire.
Similar situations occurred in many villages and towns from Tarnovo to Varna.
Some Greek who tried to incite rebellion were arrested and executed by local officials, but in many rural areas where lords had weak control, the idea of resistance spread rapidly like a virus.
On Christmas Day, 1466, a young man claiming to be a descendant of the Shishman dynasty launched a rebellion in Great Tarnovo with the support of Orthodox Christians in the city. His rallying cry was to expel heretics and restore Bulgaria.
Responders to the uprising appeared across the vast rural areas of central and eastern Bulgaria, and for a time, beacons of rebellion flared throughout Bulgaria.
"Your Highness Regent, something terrible has happened!"
Frederick was in his palace in Sofia, studying ancient texts on astrology that he had recently collected, one of his few hobbies.
Just then, his most trusted Austrian advisor, John, rushed up to him, interrupting his leisure.
"John, slow down. What happened now?"
Frederick frowned slightly. After the army had departed, Bulgaria's interior was quite empty, and he certainly did not want any further complications at this time.
"A rebellion has broken out in Great Tarnovo. The rebels took advantage of the city's weak defenses to seize it, and a large-scale peasant uprising has emerged in the eastern part of the Kingdom. It is said that the rebel leader is a descendant of the Shishman dynasty."
"Great Tarnovo?" Hearing the familiar place name, Frederick was slightly stunned for a moment before realizing that his own home had been stolen, and he anxiously pressed, "How are Anna and Rudolf?"
"Your wife and child have escaped Tarnovo under the escort of the Teutonic Order and are currently en route to Sofia."
Upon hearing this, Frederick sighed in relief. Since arriving in Bulgaria, he had almost constantly handled the Kingdom's affairs in the capital, Sofia, while his own fief, the Tarnovo Principality, had been entrusted to his wife, Anna of Saxony.
Their only child, Rudolf, was also educated by Anna.
Frederick would not blame his wife for losing Great Tarnovo; after all, the troops in his territory had also been dispatched to the Greece battlefield. With the territory's defenses depleted and the rebels launching a sudden attack, poor defense was quite normal.
Although there had been occasional disturbances in various parts of Bulgaria before, a situation where a major city was taken so quickly had never occurred, which made Frederick feel uneasy.
"This rebellion must be the work of the Ottomans. There were previous reports of Greek spies sent by the Ottomans inciting rebellion in the eastern part of the Kingdom, but I didn't expect it to come so quickly."
Frederick's words were full of anger; those accursed Ottomans seemed to revel in chaos.
"Your Highness, the most urgent task is to quickly assemble an army to quell this rebellion, otherwise, more complications may arise."
Advisor John was very worried; if the Ottomans took advantage of this opportunity to invade Bulgaria, the situation would be dire.
"We still have many well-defended fortresses on the eastern border; those rebels will find it difficult to capture them. The Ottomans have already endured many years of war, so they should not rashly attack Bulgaria. Therefore, we only need to deal with the rabble who started the rebellion.
How large is the rebel force?"
Facing Frederick's question, John shook his head and replied, "Reports from the East only say that rebels have appeared from Great Tarnovo to Varna, so their numbers are likely no less than twenty thousand."
From Great Tarnovo to Varna, which is half of the Kingdom of Bulgaria, Frederick's recently calmed mood immediately became tense again.
"It's impossible to raise another army to suppress the rebellion in such a short time! Recall the army sent to Greece? No, it's better to ask Laszlo for help."
Frederick knew that disrupting his nephew's strategic deployment would certainly draw criticism, so he immediately wrote a letter requesting aid and ordered it to be sent to Vienna as quickly as possible.
Subsequently, he began to gather troops to strengthen Sofia's defenses, waiting only for the arrival of reinforcements sent by the Emperor; then, those rebels would face their doom.