Tying directly into the previous chapter on Lothar I, this contribution looks at the earliest part of the rule of Louis II in Italy. Louis had been appointed sub-king of his father, Emperor Lothar I, in 840,by his grandfather Louis the Pious. In 844, he was sent on his first dpilomatic and military mission by his father, under the supervision of his uncle Drogo of Metz. This mission at the head of a sizeable army and group of bishops from Lothar's realm was destined to go to Rome and get Pope Sergius II in line, as he had been raised to the apostolic see without the emperor's consent. The expedition was then possibly also to go on to southern Italy and interfere in the ongoing civil war among the Beneventan Lomabards, but negotiations in Rome with the southern Prince Siconulf and Guy of Spoleto prevented that move at this point. The chapter thus shows the young king and future emperor Louis at the earliest stage of his carreer and how Lothar I paved the way for his oldest son to rule the kingdom assigned to him.

This contribution is designed to give an overview of the political history of Italy in the ninth century. As the other contributions in this voume are to be far more precise about certain aspects, the aim of this chapter is mainly to provide a grid on which the reader can get easy access to the developments in Italy in this period. The chapter thus starts with Charlemagne's policy in Italy, but then quickly moves on to Louis the Pious and his son, Lothar I. The main focus is then on the rule of Louis II, whose tenure can be seen as the pinnacle of Carolingian influence on Italian soil. An epiloge then provides the most important developments into the tenth century.

The present volume is the fruit of a small conference held in Vienna in late April 2016 under the title ‘Italy and Its Rulers in the Ninth Century: Was There a Carolingian Italy?’. It was the last event sponsored by the ERC Advanced Grant Project ‘Social Cohesion, Identity and Religion in the Early Middle Ages’ (SCIRE)1 which very successfully ran in Vienna between 2011 and 2016. Its specific aim was to bring together researchers working on Italy in the times between the death of Charlemagne in 814 and the death of Berengar I in 924, the last emperor to be crowned until 962. The scope was widened to include the period since King Pippin of Italy, Charlemagne’s second-oldest son, who was responsible for Italy until his premature death in summer 810. The ninth-century kingdom of Italy still lacks an in-depth study that avoids dealing with it merely as a time of transition. This is quite surprising, as, for example, the tenth century has received more studies that are comprehensive. The present volume aims to fill parts of this gap.

This chapter describes the institutional, political, and legal changes that the Roman episcopacy underwent during the first millennium. It sketches the historical developments that led to the emergence of the papacy as an institution, and it describes the first official papal decretals and the early collections of papal decisions. The chapter also examines the evolving ideas of Petrine and Pauline succession and of papal supremacy. Inseparably linked to those ideas was the relationship between the bishops of Rome and the ever-changing but enduring Byzantine Roman Empire. In the period under study, the papacy had to deal with many external and internal challenges, which shaped the Roman episcopacy during the first millennium and thereafter. The chapter should be read in connection with the chapters on two popes: Leo the Great (440–461) and Gregory the Great (590–604).