German bishops and archbishops were important military commanders in the Holy Roman Empire, often leading troops to battle. In the following account by Otto of Saint Blasien, the chronicler describes how a Roman army besieged Reinald, the archbishop of Cologne at Tusculum, only to be relieved by a force led by the archbishop of Mainz. The battle of Tusculum was fought on May 29, 1167 (it was also called the Battle of Monte Porzio). Archbishop Reinhald wrote a letter home describing his victory, not included here, and notes that 9000 of the enemy were killed and another 5000 captured, and even claims that none of the men on his side were killed.
In the year 1166 since the birth of Christ, Emperor Frederick, after settling the conflict between the princes, as we have mentioned, and restoring good order to the situation in Germany, assembled an army from all parts of the empire and led it into Italy, crossing the Alps for the fourth time. Then he crossed the Apennines, and, leading his army through Tuscany, he turned to the March of Ancona, and surrounded the rebellious city of Ancona with a siege. In the meantime, Reinald, the archbishop of Cologne, who had previously separated himself from the emperor on imperial business, turned against the castle of Tusculanum near Rome, as he was returning with his corps to rejoin the emperor, in order to take care of the situation there. When this was reported in Rome by messengers, the Romans, whose strength was estimated as 30,000 armed men, moved out from the entire city and suddenly besieged the archbishop in the castle, to the dishonor of the emperor. As soon as this was reported to the emperor at Ancona, he assembled the princes and asked them whether or not he should give up the siege of Ancona and go to the aid of the archbishop. A few of the princes, most of them of the laity, who feared the spread of unfavorable rumors that would result from a lifting of the siege, advised against it. Angered by this agreement of the princes, because the lay princes had such small regard for him and his colleagues or abandoned them in danger, the stately archbishop of Mainz, Christian, called together his men and others whose aid he could enlist by pleas and rewards. He assembled 500 knights and 800 mercenaries, appropriately equipped for war, and moved out toward Tusculanum against the Romans, in order to relieve the archbishop. When he arrived there and had pitched his camp opposite the Romans, he sent emissaries to them to request peace for that day only to allow his army to rest, recalling the virtue of the noble attitude that was characteristic of the ancient Romans. In this way, he hoped to win his demands from them. But the Romans themselves, completely unlike the ancients in this and all other respects, answered that they would not grant his request but arrogantly threatened that on this day they would give him and his entire army to the birds of heaven and the wild animals of the earth to eat. Giving up the siege, they formed 30,000 warriors in line of battle against 500 German knights. But the archbishop, completely unshaken by the answer he had received from them – for he was not inexperienced in the troubles of war – with great energy encouraged his men for battle by promises and threats. Even though their number was very small in comparison with their opponents, he knew they were battle-hardened fighters. He warned them in noble words that they could not place their hope in flight, since they were too distant from their fatherland and the emperor’s army to be able to flee, but, mindful of their inherent courage and of the cowardice that was natural to their enemies, they should fight for their lives with all their strength.
But when he saw that the knights were filled with German fury (“animositate Teutonica”) – for his exhortation had injected a certain invincible courage in their hearts – he formed his lines and specified precisely which ones were to fight at first, which were to break into the fighting enemy forces from the flank, which ones were to bring help to those in trouble in the fight, while he himself took position where he could bring help with the most highly selected men. And now he moved into the fight against the Romans with raised banners and widely deployed cohorts, placing his hope in God. The archbishop of Cologne, however, armed himself and the garrison of the castle and all his men, a number estimated as 300 well-armed knights, in order to be able to give help under any circumstances, and he remained calmly in the castle until the start of the battle. After the battle had begun and the lances were broken at the first clash of the armies, the fight was carried on with swords, while the archers on both sides obscured the light of day with their arrows as if they were snow flakes. And behold, the archbishop of Cologne, breaking out of the castle with his eager knights, attacked the Romans from the rear and pushed against them courageously, so that they were surrounded on all sides, attacked from front and rear. While the Romans therefore were fighting only with the weight of their mass, Bishop Christian with his men penetrated their battle line from the flank, tore the middle of their formation apart, and covered with blows the enemy that was thus skillfully separated into three groups. After many had been killed and a number taken prisoner, the defeated Romans took to flight and, pursued by their conquerors up to the city, they were cut down in the bloodiest slaughter. After they had called back their knights from this butchery, the bishops returned to the battlefield and spent that night celebrating with the greatest joy.
In the morning the Romans hastened out to the battlefield to recover the corpses of their fallen. They were driven to flight by the bishops, who sent their knights out against them, and returning toward the city, they barely escaped death. Finally, they sent emissaries to the bishops to beg that they be allowed, for the love of Saint Peter and respect for Christianity, to recover their dead. The bishops granted this plea on the condition that they would count the number of men on their side that were killed or captured in this battle and would report this to them personally in writing with a sworn guarantee of their truthfulness, and that they could peacefully recover their dead for burial only after complying with this condition. When they went about this accounting, they found the number of some 15,000 of their men who had been killed or captured in this battle. After receiving permission, they buried the remains of their dead, which they recovered with loud lamenting.
From Monumenta Germanica Historica Scriptores SS., 20.