…Placentia (modern Piacenza), where he suffers a severe defeat.

The Alamanni forces push past the disordered Romans at Placentia, …

Pope Adrian II maintains the policies of his predecessor Nicholas I, but with less energy.

The reign of Lothair, King of Lothairingia, had been chiefly occupied by his efforts to obtain a divorce from his wife Teutberga, a sister of Hucbert, abbot of St. Maurice (d. 864) and daughter of the Bosonid Boso the Elder, and his relations with his uncles Charles the Bald and Louis the German have been influenced by his desire to obtain their support for this endeavor.

Although quarrels and reconciliations between the three kings have followed each other in quick succession, in general it may be said that Louis favors the divorce, and Charles opposes it, while neither has lost sight of the fact that Lothair had no sons to inherit his lands.

Lothair, whose desire for the divorce is prompted by his affection for his mistress, Waldrada, had put away Theutberga, but Hucbert had taken up arms on her behalf, and after she had submitted successfully to the ordeal of water, Lothair had been compelled to restore her in 858.

Still pursuing his purpose, he had won the support of his brother, Emperor Louis II, by a cession of lands and obtained the consent of the local clergy to the divorce and to his marriage with Waldrada, which took place in 862.

A synod of Frankish bishops had met at Metz in 863 and confirmed this decision, but Teutberga fhad led to the court of Charles the Bald, and Pope Nicholas I had voided the decision of the synod.

An attack on Rome by the emperor was without result, and in 865 Lothair, threatened with excommunication and convinced that Louis and Charles at their recent meeting had discussed the partition of his kingdom, had again taken back his wife.

Teutberga, however, either from inclination or compulsion, has now expressed her desire for a divorce, and Lothair has gone to Italy to obtain the assent of the new pope.

Placing a favorable interpretation upon the words of the pope, he sets out on the return journey, when he is seized with fever and dies at Piacenza on August 8, 869.

He leaves, by Waldrada, a son Hugh, who is declared illegitimate, and his kingdom is divided between his uncles Charles the Bald and Louis the German by the Treaty of Meerssen.

The forces of Rudolph, Adalbert, and Berengar of Ivrea meet those of Berengar on July 29, 923, and defeat him in the Battle of Fiorenzuola, near Piacenza.

The battle is decisive and Berengar is de facto dethroned and replaced by Rudolf.

The reprimands of the Pope, couched as they are in such an unprecedented form, infuriate Henry and his court, and their answer is the hastily convened national council in Worms, Germany (the synod of Worms), which meets on January 24, 1076.

In the higher ranks of the German clergy Gregory has many enemies, and a Roman cardinal, Hugo Candidus, once on intimate terms with him but now his opponent, had hurried to Germany for the occasion.

All the accusations with regard to Gregory that Candidus could come up with are well received by the assembly, which commits itself to the resolution that Gregory has forfeited the papacy.

In one document full of accusations, the bishops renounce their allegiance to Gregory.

In another, Henry pronounces him deposed, and the Romans are required to choose a new pope.

The council sends two bishops to Italy, and they procure a similar act of deposition from the Lombard bishops at the synod of Piacenza.

…Piacenza, and …

The turmoil of these past several years has disrupted normal political life and made the pilgrimage to Jerusalem, finally captured by the Seljuqs in 1071, difficult and often impossible.

Stories of dangers and molestation reach the West and remain in the popular mind even after conditions have improved.

Further, informed authorities begin to realize that the revived power of the Muslim world now seriously menaces the West as well as East.

It is this realization that stimulates official and organized action.

By the time Alexios had ascended the throne in Constantinople, the Seljuqs had taken most of Asia Minor.

Alexios has been able to secure much of the coastal regions by sending peasant soldiers to raid the Seljuq camps, but these victories have been unable to stop the Turks altogether.

As early as 1090, Alexios had taken reconciliatory measures towards the Papacy, with the intention of seeking western support against the Seljuqs.

In March 1095, his ambassadors appear before Pope Urban II at the Council of Piacenza.

The Eastern Emperor’s appeal appeal for Western aid comes at a time when relations between the Eastern and Western branches of the Christian world are improving.

Difficulties between the two in the middle years of the century had resulted in a de facto, though not formally proclaimed, schism, and ecclesiastical disagreements had been accentuated by Norman occupation of formerly imperial areas in southern Italy.

Robert Guiscard's campaign against the Greek mainland has further embittered the imperial Greeks of Constantinople, and it is only after his death that conditions for a renewal of normal relations between East and West became reasonably favorable.

Envoys of the emperor thus arrive at the Council of Piacenza in 1095 at a propitious moment; and it seems probable that Pope Urban II views military aid as a means toward restoring ecclesiastical unity.

The Pope is impressed by Alexios's appeal for help, which speaks of the suffering of the Christians of the east and hints at a possible union of the eastern and western churches.

Pope Urban was concerned with increasing restlessness of the martial nobility in Western Europe, who, currently deprived of major enemies, are causing chaos throughout the countryside.

Alexios's appeal offers a means not only to redirect the energy of the knights to benefit the Church, but also to consolidate the authority of the Pope over all Christendom and to gain the east for the See of Rome.

Conrad attends the Council of Piacenza and confirms his stepmother Eupraxia's accusations that Henry IV is a member of a Nicolaitan sect, participates in orgies, and had offered Eupraxia to Conrad, stating that this was the reason for his turning against his father.

The Diet of Roncaglia, held in 1158 near Piacenza as a general assembly of the nobles and ecclesiasts of the Holy Roman Empire and representatives of each of the fourteen cities of the future Lombard League, follows a series of raids carried out by the forces of Frederick Barbarossa in Italy that have forced the submission of Milan.

The Emperor wishes to establish his rights as feudal sovereign in the face of the growing independence of trading cities, which had won charters of municipal privilege during the earlier periods of strife between Papacy and Empire.

The determination of the respective rights of the parties is left to four jurists from Bologna, the home of the great law school founded in 1088.

The lawyers' decision favors the emperor, judging that his rule is by divine right, thus restoring the Imperial rights established since the period of nascent trade under rule of Emperor Otto.

The lawyers proceed to define taxes, tolls, and exactions of various kinds to be imposed on trade.

The Diet sees the establishment of imperial officers in the cities of northern Italy, and the beginning of the long struggle with Pope Alexander III.

Frederick convokes a general Diet of the Empire at Piacenza in 1236 to force Italian cooperation, then annexes church lands, prompting his third excommunication and a renewal of the war between Empire and Papacy.

Imperial forces attack Piacenza in 1245.

Sforza, returning to the siege of Piacenza and finding the city not likely to crumble by starvation, resolves to storm it.

Employing cannons in an almost unheard-of manner, he opens up a breach in the walls and sacks the city.

The news of this sack is greeted by three days' rejoicing in Milan.