Bologna finally decided to try to conquer Forlì. So the Bolognese organized a regular army to march against the Romagna city, besiege it and subjugate the Romagna lands to the church.
This caused the people of Forlì to become aware of the danger they were in and they called upon Guido da Montefeltro to help them, who was known as "il Feltrano", an unparalleled Ghibelline, who was elected captain of the arms of Forlì and who prepared to fight against the Bolognese.
In 1273 the Bolognese army, ready to fight, set out along Via Emilia towards Forlì, to besiege it and force it to capitulate, but they found it very organized and equipped with numerous soldiers.
Furthermore, the Bolognese army was also made up of Ghibellines and Guelphs, and the people of Forlì took advantage of this during the first siege to establish friendships and make agreements with the Ghibelline Lambertazzi, which lead to future military and political alliances against the Geremei.
The Lambertazzi then pushed for peace, but the Geremei imposed conditions of surrender that were unacceptable to the people of Forlì.
Not even King Edward I of England, passing through Romagna returning from a crusade in the Holy Land, was able to reconcile Bologna and Forlì. This is because the eternal conflict was not between the two cities, but between Guelphs and Ghibellines.
So, finally, after two months of useless siege, the Bolognese decided that they needed many more troops to conquer it and withdrew without having caused even one injury to the Forlì people.
Instead the people of Forlì took advantage of the retreat of the Bolognese to take back Faenza, which after the death of Frederick II had returned to the Guelphs.
In this case they left the city with the excuse of pursuing the Bolognese army as far as Cosima, a town between Forlì and Faenza. The people of Faenza, seeing the people of Forlì approaching, closed the gates to prevent their entering, but il Feltrano had secretly agreed with some Ghibellines from Faenza and, with the excuse of wanting to continue his march towards Bologna, pretended to want to make camp in the countryside around Faenza without destroying or interfering in that land, so as not to raise suspicion.
During the night, with the help of the Acciarisi Ghibelline family,
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Finally, Guido da Montefeltro elected two Forlì imperial podestàs for Faenza
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8. The Bolognese guerilla war
Learning of the fall of Faenza into Ghibelline hands, the Bolognese began to fear the Lambertazzi had planned the move so as to bring the Forlì troops closer to Bologna.
Therefore, the following year, they decided to send another army back to Romagna with the Bolognese carroccio
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When the Bolognese set out with the army, the Lambertazzi, regardless of the consequences of such a gesture, suddenly decided to attack the Bolognese mayor directly inside the city before he left with the army, while the Forlì Ghibellines advanced from Faenza as far as the walls of Bologna to give him their support.
This immediately, ignited a guerrilla war.
The gates of Bologna were closed to prevent the entry of the Forlivese, but when a fight broke out between the Lambertazzi and Geremei, the people abandoned all neutrality and sided with the Guelphs to expel the Ghibellines from Bologna and began attacking the Lambertazzi inside the city.
Somehow the people of Forlì managed to enter,
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Thus between April and May 1274 a guerrilla war between the two factions began in Bologna that lasted, without respite, almost two months.
Guelphs and Ghibellines were grouped inside the walls and neighborhoods were divided, which challenged each other to the bitter end.
In those days anything could happen. There were clashes on both sides at all hours of the day and people were even murdered at night, and later found in ditches or floating in streams the next morning.
Bologna was in the balance and seemed to have fallen into the hands of the Ghibellines.
In the end, in order not to capitulate, the Bolognese Guelphs called upon a large reinforcement of Lombard Guelphs to support the city.
The Guelphs prevailed, while ten Lambertazzi leaders were captured and imprisoned during a coup by the mayor of Bologna, who had summoned them with an excuse to discuss their surrender.
The Lambertazzi realized there was no escape and had to agree to come to terms and leave Bologna.
Thus, on the morning of 2 June 1274, after months of guerrilla warfare, in the midst of an unreal silence, there was an exodus of twelve thousand armed Ghibellines with wives, children and supporters in tow, who left Bologna without anyone daring to stop them, leaving almost half the city empty in one sweep.
They headed along the Via Emilia in the direction of Faenza, previously occupied by the inhabitants of Forlì, which was ready to welcome them.
9. The Lambertazzi exiles in Romagna
The long Ghibelline line, embittered but not defeated, headed towards Faenza, recently cleared by the Guelphs, which was ready to welcome them under the banner of the Forlì imperial eagles.
Some of them with wives and children permanently sheltered in Forlì, but the bulk of the Bolognese Ghibellines were housed in the newly conquered Faenza.
They placed themselves under the command of the Forlì captain Guido da Montefeltro and quickly began to reorganize to fight the Bolognese Guelphs again.
The Bolognese, after the violence of those events and having recovered strength after the expulsion of the Lambertazzi, took courage from the situation and decided to organize an attack on Faenza and Forlì again, to defeat the Ghibellines of Romagna once and for all.
But the Ghibellines from Romagna, even if numerically inferior, were more combative and had a very skilled military captain, and Bologna and the Guelphs would soon find out about him for themselves.
10. Capture of the Bolognese carroccio
The following year the Bolognese, believing that the Lambertazzi were preparing to return from Faenza to Bologna, decided to anticipate them and remove them from Romagna once and for all.
The Bolognese made a conducted a few raids in the Faenza territories to test the strength of the Ghibellines. Subsequently they decided to put together an army that was reinforced by Guelphs from Lombardy, Imola, Cesena and Ravenna.
Once assembled, they left to march towards Faenza to free it from the Lambertazzi so they would have a stronghold from which to attack Forlì.
The people of Forlì and the Lambertazzi, knowing this, did their utmost to stop them.
They gathered a sizeable Ghibelline army and set about reinforcing the Faenza and Forlì defenses, while Guido da Montefeltro managed to gather a series of worthy Ghibelline commanders under him, who came from various parts of Tuscany and Romagna, followed by their troops.
Those who came under the Ghibelline insignia were Guglielmo de' Pazzi of Valdarno, commander of the Tuscan outcasts, Mainardo Pagani da Susinana, a Guido Novello and sons, Bandino, Tancredi, Ruggiero and Tigrino of the Guidi counts, lords of Modigliana with their people, to whom they joined the Forlì people Aliotto Pipini, Superbo Orgogliosi, Teodorico Ordelaffi
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On 13 June 1275 as soon as the news came that the Bolognese had crossed the San Procolo
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Having come within sight of the Bolognese, Count Feltrano with the help of the Ghibelline commanders Maghinardo Pagani, Theodoric degli Ordelaffi, and other captains of the Lambertazzi, organized the troops for war and made a speech to incite them to battle.