The city, from time immemorial the meeting-ground for the best elements in Italian society, had become in the early Middle Ages the one bulwark between the Italian middle-classes and a particularly lawless form of feudalism; and it had served this purpose well. The number of these cities, their population and resources, the luxury of the citizens, the splendour of the palaces and public buildings, were the admiration of all Europe at a time when the Flemish burghers still lived in wooden houses and the Flemish cities were still rudely protected by palisades and earthen ramparts. Nature had done much for Italy. Thanks to the central situation of the peninsula, the trade between Northern Europe and the Mediterranean converged upon her seaports and the Alpine passes which stand above the valley of the Po. The untiring industry of Italian capital and labour made Lombardy and Tuscany the homes of textile manufactures, of scientific cultivation, of banking and finance. In every port of the Levant, the Aegean and the Black Sea, the shipmen and merchants of Venice, Benoa, and Pisa hunted for trade like sleuth-hounds, and fought like wolves to secure a preference or a monopoly. By land and sea the rule of life was competition for territory and trade. War was a normal and often a welcome incident in the quest for wealth; few Italians were free from the belief that conquests are a short cut to prosperity, that trade follows the flag, and that the gain of one community must be another's loss. Within the city walls, class strove with class and family with family. Riot, massacre, and proscription were the normal instruments of party warfare; minorities conspired from fear of proscription, and majorities proscribed in order to forestall conspiracy. Boundless, indeed, was the vitality of republics which, under such conditions, not only throve, but also held at bay the ablest sovereigns and the most formidable troops of Europe.
The best and the worst features of the communal regime are illustrated in the resistance of the Lombard cities to Frederic Barbarossa, the first Emperor who formulated and applied to Italy a scheme of absolutist government. Between 1154 and 1176 the Lombards turned the course of history. They prepared the way for Innocent III to plant his foot upon the necks of kings, and for Innocent IV to destroy the House of Hohenstauffen. That this would be the result of their stand for liberty, neither they nor the other parties to the struggle could foretell. But on both sides it was felt that the greatest issues were at stake. The question was whether Italy should, once for all, accept a German yoke; whether the Papacy should become a German patriarchate; whether free institutions, both in Church and State, should give place to a bureaucracy.
The question did not take this shape from the beginning. When Frederic first intervened in Lombardy he came to protect the smaller cities against the imperialist ambitions of Milan, to restore the public peace, to investigate innumerable complaints of force and fraud. Many of the cities hailed him as a deliverer; against him were only the clients of Milan, or those who, on a humbler scale, aspired to emulate her policy. Even so it was no easy matter to chastise the most insignificant of the contumacious communes; and Milan, who refused point-blank to give satisfaction for her lawless acts of conquests, or even to renounce what she had won, could not safely be attacked.
Two circumstances were against the Emperor. Any war against the Lombards must be a war of sieges; but the military science of the age was more skilful in defence than in attack. And no war could be carried to a prosperous conclusion without Italian help; for it was impossible to interest the German princes in the wars of Italy, or to exact substantial help from them. The first of these difficulties Frederic Barbarossa never overcame. With the second he was more successful in the middle period of the conflict (1158-1162); and it was then that the representatives of Lombard independence were most nearly overwhelmed.
In 1158 he came back from Germany to besiege Milan, having carefully concluded treaties with her rivals in Lombardy, in the Mark of Verona, in Emilia and the Marches. With their help he starved the impregnable city into a surrender on terms dictated by himself. In these there was nothing to excite suspicion or alarm. It was a matter of course that the Milanese should take the oath of allegiance and emancipate the enslaved cities. He stipulated further for a palace in the city, and for the restitution of all imperial prerogatives (regalia) which the consuls had usurped; but the full import of these latter articles only became clear some two months later, when he announced his future policy at a Diet held on the plain of Roncaglia. He disclaimed the intention of ruling as a tyrant, but demanded that his lawful rights should be respected. As guardian of the public peace, he would permit no private wars to be waged and no leagues to be formed among the cities. As lord of the land, he claimed, under the title of regalia, a formidable list of rights and dues which the jurists of Bologna had compiled at the expense of much historical research. It included the nomination of the highest magistrate in every city; the supreme jurisdiction in appeals and criminal causes; the control of mints, markets, and highways; and rights of purveyance and taxation. Some of these had been in abeyance from time immemorial; most of them had been exercised by the cities for more than fifty years. Frederic held that no prescription could avail against the Crown; and, if this attitude seemed more appropriate to a Justinian than to a King of the Lombards, there was still something to be said for his claims on grounds of public policy. Till a strong monarchy was re-established in Italy, city would oppress city, and the strong would rob the weak. But such a monarchy could only be maintained if an ample revenue were assured, and if the powers arrogated by the communes were curtailed.
Even those cities which had originally supported Frederic began to waver when they saw the logical consequences of his policy. They were not disposed to cavil at any measures that he might take against Milan. But to deal with friend and foe on the same principles struck them as injustice. To run the risk of enslavement by a neighbour was an evil; but it was worse to lose for ever the prospect of enslaving others. And what guarantee was there that the new absolutism, once firmly in the saddle, would always be benevolent, or would always be represented by officials of integrity? The claims of the Emperor might be in a sense historical; but the cities knew, if he did not, that the so-called restoration of regalia was in effect a revolution. The time was nearly ripe for general defection; loyalty was strained to breaking-point when Frederic began to appoint for each city a resident commissioner (podesta), empowered to exercise the regalian rights and to collect the revenue accruing from them. But Milan was still feared and hated. When she alleged that her recent treaty of capitulation was infringed by the decrees of Roncaglia, and when she expelled the envoys whom Frederic had sent to instal a podesta, the other cities rallied to the imperial cause. There was one notable exception. The little commune of Crema had been ordered to destroy her walls; she refused, and made common cause with her great neighbour.
The imperial ban was issued against both cities (April 1159); troops were hurriedly called up from Germany, and contingents were obtained from the Italian allies, until Frederic had in the field a force estimated at 100,000 men. But for six months he was held in check by the resistance of Crema, which he had planned to reduce with a small force while the main bulk of his levies were gathering for the siege of Milan. The attack on Crema was cordially seconded by the citizens of the neighbouring Cremona, who gave their assistance in diverting the watercourses which ran through the city, and lent Frederic the most famous of living engineers to make his siege-machines. Crema was completely invested; and every known method of assault was tried. The moat was filled with fascines, and movable towers of wood, so high as to overtop the battlements, were brought up to the walls; which were also attacked with rams, and undermined by sappers working in the shelter of huge penthouses. But breaches were no sooner made than repaired; every scaling-party was repulsed; and the defenders derided the Emperor in opprobrious songs. For once in his life he descended to bluster and ferocious inhumanity. He swore that he would give no quarter, he executed captives within sight of the walls, and he suspended his hostages in baskets from the most exposed parts of the siege-towers. Fortunately for his fame he relented, when hunger and the desertion of their master-engineer compelled the Cremesi to sue for terms. They received permission to depart with as much property as they could carry on their backs. The rest fell to the imperial army; and the men of Cremona were commissioned to demolish the city, which they did with a goodwill. The turn of Milan followed; the Emperor, warned by experience, fell back upon the slow and costly, but irresistible method of blockade. At the end of eight months (May 1161-Feb. 1162) the city was surrendered, evacuated, and condemned to destruction—a sentence which it was found impossible to execute completely, so solid were the ramparts and so vast the buildings they enclosed. For the moment all resistance seemed at an end. The policy outlined at Roncaglia could at length be put in force through the length and breadth of Lombardy; and Frederic departed for Germany, leaving trustworthy lieutenants to complete the vindication of his Italian rights. It only remained to try conclusions with a recalcitrant Pope and the evasive Normans of the South. The Emperor already saw himself in imagination the master of Italy, and even of the Western Mediterranean. Five years passed without bringing him nearer to his goal. Then Frederic returned to effect the expulsion of Alexander III from Rome. He succeeded in this object, and was crowned in St. Peter's by the anti-Pope of his own choosing (August 1167). It was the highest point of his fortunes, and the calamities which followed were so unforeseen and terrible that contemporaries saw in them the hand of God. While he was still in Rome, a pestilence broke out which cost him two thousand knights and his best counsellors. He was forced to fly from the infected city. On his way to the north he found the road barred by a new and formidable coalition. The Lombard League had come into existence—an alliance organised by Cremona, hitherto the staunchest of imperial allies, and closely linked with Venice, which Frederic had regarded as a negligible quantity. Of the intentions of the League there could be no doubt. The members were already engaged in the rebuilding of Milan; they had admitted to their inmost councils a legate of Alexander III; they announced that they would only render to the Emperor his ancient and undoubted rights. Frederic would not trust himself in their vicinity. Accompanied by a handful of knights he escaped ignominiously to the north, taking a circuitous route through Savoy. The Leaguers no longer troubled to mask their true intentions. As a token of their unity they built the city of Alessandria, named after Frederic's bitterest enemy, the lawful Pope; and they solemnly repudiated the appellate jurisdiction of the imperial law-court (1168).
Six years elapsed before Frederic could return to demand satisfaction, and even then he could only muster some eight thousand men. From October 1174 to April 1175 he was engaged, first in besieging Alessandria, and then in making fruitless overtures to the League for a compromise. By the end of 1175 he was virtually blockaded in Pavia with a dwindling remnant of his army. Reinforced in the spring, he made a rapid march on Milan, in the hope of taking unawares the headquarters of the League. But the Lombards were forewarned, and met him, at Legnano (29th May 1176), with a force outnumbering his by more than two to one. The battle was hotly contested. The Lombard vanguard, composed of cavalry, scattered before the onslaught of the Germans. The Emperor then led a charge which penetrated to the centre of the enemy's position. Here was the banner of Milan, mounted on a triumphal car (carroccio) and guarded by picked burgesses, who had sworn to defend their trust to the death. Round them the fighting raged for hours; the Germans made no impression on their ranks, and by degrees the Lombard troops who had fled returned to renew the battle. At length the imperial standard-bearer was slain, and Frederic himself unhorsed. Thinking all was lost, the imperialists fled confusedly towards Pavia, which they reached after suffering more loss in the flight than in the battle. Frederic, cut off from his followers, only escaped capture by hiding for some days until the road to Pavia was clear.
Legnano was no overwhelming catastrophe, but it was ominous that citizen levies had defeated German knights in a fair field. Frederic's counsellors insisted that it was foolhardiness to pursue the war interminably, when at any moment the papal interest might gain the upper hand in Germany. Peace must be made at any cost with Alexander, and he would accept no peace from which the Lombards were excluded. Frederic yielded to the inevitable with a good grace. A treaty was concluded with the Pope in the same year (November 1176); a few months later, a six years' truce with the Lombards was arranged at Venice; and at Constance, in 1183, this was converted into a lasting peace. In form there was a compromise. The cities, while retaining the regalia and the free election of their consuls, recognised their allegiance to the Emperor and his appellate jurisdiction. In reality the Emperor had surrendered everything of value, and the cities ignored any stipulations in the treaty which were unfavourable to them.
So matters remained until Frederic II, the grandson of Barbarossa, having firmly established himself in his Sicilian heritage, began to meditate a closer union between his dominions north and south of the Alps. The better to secure his communications with Germany, he prepared to enforce in Lombardy the imperial rights reserved at Constance (1226). At once the dormant Lombard League revived. The Alpine passes were so effectually blockaded that Frederic was left entirely dependent on his Sicilian forces. He turned the flank of the League at length, by an alliance with Ezzelin da Romano, the tyrant of Verona, which gave him access to the Brenner pass; but the League retaliated by lending support to his rebellious son, Henry, King of the Germans. So began another war in Lombardy. Legnano was brilliantly avenged on the field of Cortenuova (1237), where the Emperor routed the Milanese and captured the carroccio, the symbol of their independence. But he, like his grandfather, was worn out by the difficulties of siege warfare; and in 1240 he turned southward to reduce the States of the Church. One more attempt he made on Lombardy in the winter of 1247-1248. But a disastrous fiasco destroyed his hopes and gave a mortal blow to his prestige. For five months he blockaded Parma, and the city was at the last gasp, when he imprudently dismissed a part of his troops. The garrison saw their opportunity, and made a desperate sortie while the Emperor was absent on a hunting expedition. They surprised and burned the strongly fortified camp which he had named Victoria; his baggage and even his crown jewels were captured; more than half of his army were slain or taken, and the rest fled in confusion to Cremona (18th February 1248). It was necessary for Frederic to beat a retreat, and he appeared no more in Lombardy. His son Enzio, whom he left to represent him, was captured next year by the Bolognese and sentenced to perpetual captivity.