This chapter is devoted to the pontificate of John VIII (872–882) and the significant physical threat to the city of Rome posed principally although not exclusively by Muslim marauders from North Africa, particularly in the aftermath of the death of Emperor Louis II in 875. Papal efforts to find new military champions were largely unsuccessful, although a significant victory was scored by the Byzantine imperial fleet at the mouth of the Tiber in 880. John VIII also constructed fortifications to defend the church and monastery of San Paolo fuori le mura, hoping to present a repeat of the sack of 846. Although the papal court is known to have been a hotbed of intellectual activity, little has survived from this era in the way of material culture except for the conversion of the temple of Portunus into the church of Santa Maria de Secundicerio by a senior lay official, Stephen secundicerius. Surviving fragments of its mural decorations reveal the influence of both apocryphal texts about the life of Mary as well as contemporary Byzantine hagiographic literature. This leads to a discussion of the place of origin of certain contemporaneous Byzantine manuscripts which share the same style as the murals, most notably the Paris Sacra Parallela (BnF gr. 923).

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.

Successive Carolingian rulers found managing the relationship with their adult sons challenging. The father-son relationship between Lothar I and his oldest son, Louis II, offers a valuable perspective on the forces at work in the relationships between senior and junior rulers more widely, as well as the specific challenges involved in ruling Italy from Francia. While our sources generally emphasize obedience to the father, successful father-son partnerships also had reciprocal elements, and involved effort on both sides. Lothar I and Louis II seem to have maintained a stable and productive relationship between 840 and Lothar’s death in 855. Public affirmation of the partnership between father and son, Lothar’s gradual delegation of power to Louis II, and the absence of key triggers for rebellion, such as a direct threat to Louis II’s position, help account for this success. A tight-knit lay and ecclesiastical elite that spanned both courts also helped stabilize the relationship. When positive factors assisting the father’s control were absent, and negative factors prompting rebellion on the part of the son were present, Carolingian father-son relationships could and did go awry, as in Louis the Pious’s case.