Depiction of the Ottonian family tree in a 13th-century manuscript of the Chronica sancti Pantaleonis

The lack of a crowned emperor from 925 to 961 was largely due to the reluctance of the Theophylact popes to play their last card in their game against increasingly powerful kings of Italy. Hugo of Arles had been succeeded by Berengar II, margrave of Ivrea, who, by 959, had conquered Spoleto and was threatening Rome as the Lombards had done two centuries before. The best chance of relief appeared to be the Ottonians, who followed the Carolingians in eastern Francia from 919. Otto I had already made two botched attempts to assert authority in northern Italy between 951 and 952. He spent the next decade consolidating his hold over Germany, whilst carefully cultivating contact with bishops fleeing the troubles in Italy. Otto was determined to present himself as liberator, not conqueror, and thus worthy to be crowned emperor. His great victory over the heathen Magyars at Lechfeld in 955 convinced many contemporaries, including Pope John XII, that Otto was divinely favoured. Despite being unable to capture Berengar, Otto’s invasion of northern Italy succeeded in 961 and he was crowned emperor on 2 February 962.

Otto’s coronation did not ‘refound’ the Empire, nor create a new empire, since a sense of the original Carolingian realm had persisted and there had been plenty of individual emperors after Charlemagne. Nonetheless, his coronation was a significant event and clearly intended to put papal-imperial relations on a new, improved footing. To this end, Otto issued his own charter (the Ottonianum), confirming the ‘donations’ of Pippin and Charlemagne of extensive lands in central Italy to sustain the pope. As with his predecessors, Otto envisaged these lands remaining under his suzerainty. He likewise bound himself to protect the pope, to whom he transferred large amounts of gold and silver, receiving numerous holy relics in return for his programme of Christianization north of the Alps.

Otto’s ‘Roman expedition’ (Romzug) lasted three years and already displayed all the features shaping subsequent imperial interventions in medieval Italy. The convergence of interests facilitating Otto’s coronation was insufficiently stable for prolonged papal-imperial collaboration. Emperors wanted popes to possess sufficient personal integrity not to demean the imperial honour they conferred, but otherwise to be pliant executors of the emperor’s will. In Otto’s case, this included the controversial elevation of Magdeburg to an archbishopric. Like his successors, Pope John XII wanted a protector, not a master, and he rebelled against the ‘Frankenstein’s monster’ of Ottonian emperorship by conspiring with Berengar and the Magyars in 963. The next moves established the template for subsequent emperors towards disobedient pontiffs. Otto returned to Rome, while John fled to Tivoli. After a brief exchange of letters failed to restore harmony, Otto convened a synod in St Peter’s, which deposed John on the grounds of murder, incest and apostasy – a charge sheet sufficiently grievous to justify the first ever deposition of a pope, and one that became standard for such actions in the future. Otto confirmed Lothar I’s papal constitution of 824, allowing the Roman clergy a fairly free choice in electing Leo VIII as replacement in December 963.

Deposition was the easy part. As Otto and his successors soon discovered, it was extremely hard to maintain their own pope without firm local support, which, for the next century or so, meant the backing of the Roman clans, Italian lords and bishops. John was still at large, creating a papal schism that threatened the integrity and legitimacy of the church. The Romans rebelled as soon as Otto left their city in January 964, allowing John to return and hold his own synod to depose his rival. Leo was restored by force later that month, expelling John, who died in May – allegedly in the arms of a married woman, another story typical of the mudslinging during later papal schisms. What followed merely underscored the intractability of the problem. The Romans elected Benedict V as their own anti-pope. Enforcement of Leo VIII was now a matter of imperial prestige. Otto besieged Rome until the starving inhabitants handed over the unfortunate Benedict, who was demoted and packed off as a missionary to Hamburg. Otto sent two bishops to oversee a new election following Leo’s death in March 965, but the successful candidate was in turn expelled by another Roman revolt nine months later. The emperor was obliged to return personally, crushing Roman opposition in December 966. The socially inferior were executed, while the rich were exiled. Those who had died in the meantime were disinterred and their bones scattered in what was clearly intended as exemplary punishment.

Subsequent opposition drew an equally harsh response. The leader of the Crescenti clan was beheaded and hung by his feet along with 12 supporters in 998. Simultaneously, anti-pope John XVI was blinded, mutilated and forced to ride through Rome seated backwards on a donkey. A riot after Henry II’s coronation in Pavia as king of Italy in 1002 ended in a massacre by imperial troops in which the city burned down. Further rioting after the imperial coronation of 1027 prompted Conrad II to force the Romans to walk barefoot, though this time they were spared execution. This ‘German fury’ (furor teutonicus) reflected general attitudes to justice in the Empire, which permitted harsh punishment of those who ignored opportunities to negotiate, or who rebelled having been previously pardoned. It also betrayed the basic strategic weakness of the imperial presence in Italy throughout the Middle Ages. Rome was not a pleasant billet for an imperial army. The nearby pestilent marshes made their presence felt each summer through malaria epidemics. That of 964 killed the archbishop of Trier, the duke of Lorraine and a sizeable part of Otto’s army. Campaigns in southern Italy often encountered the same problem: malaria killed both Otto II (983) and Otto III (1002), while Conrad II lost his wife and most of his troops to disease in 1038. Losses were hard to take, because Ottonian and Salian armies were quite small. While they did have some capacity for laying sieges, Italy was a land of numerous, well-fortified cities. Violent shock and awe appeared a quick fix to these problems, but as later regimes have discovered, it generally alienated local support and discredited those who used it.

The Ottonians could usually muster armies of 2,000–8,000 . Practical difficulties of movement and supply inhibited large troop concentrations for long periods. A royal army would be composed from the king’s own retinue and those of his lords who were close allies or who had answered his summons. The king’s force would be supplemented by contingents provided by the lesser lords and communities of the immediate area where it was operating. Larger numbers of less-experienced and poorly trained men could be summoned locally for specific tasks, especially if major sieges were undertaken. These numbers grew largely thanks to the rise in population and production across the eleventh century. Frederick I’s army on the Third Crusade in 1190 was considered huge by contemporaries; it probably numbered 15,000 including 3,000 knights – still far short of the hundreds of thousands some chroniclers claimed.

It is unlikely that Ottonian commanders needed to read transcriptions of late Roman military manuals in order to know how to fight; their Slavic and Magyar opponents certainly did not, yet were frequently successful. It is highly speculative to blame Ottonian defeats on supposed failure to follow such advice, while attributing successes to allegedly having done so. Later graduates of European military academies could make elementary mistakes, despite their formal training. In addition to oral tradition and actual experience, tasks like economic management and the self-confidence that generally comes with elevated social status would all have prepared Ottonian nobles for command. In short, change across the period from 800 to 1100 was by degrees rather than absolute. Written culture may have contracted around 900, but had never been widespread, while the level of contraction itself has been exaggerated.

Few written documents were intended as universal laws. General laws were already considered fixed by moral and religious absolutes that could not be altered by mortals. Most documents issued in the name of German kings before early modernity were charters (Urkunden) regulating local, specific circumstances, and are better understood as ‘privileges’ rather than ‘laws’. They illustrate how much royal activity was reactive, rather than planned: charters were usually issued at the request of their recipient. Written documentation had yet to assume precedence over other forms of legitimation like custom. Except for intellectual exchanges between scholars, during the Middle Ages most letters were destroyed after they had been read, in contrast to early modernity, when even mundane items such as bills and receipts were often preserved. When Frederick I wanted to know how to greet Pope Hadrian IV in 1155, he asked the oldest princes in his camp who had been present at the last imperial-papal meeting 22 years earlier. Their recollections carried equal weight with formal recorded protocols. The relatively low volume of paperwork reduced the potential for conflict by making inconsistencies between claims and practice less obvious.