Since the fall of the Roman Empire in pre-medieval era, Italy couldn’t gain the status of being an entirely independent kingdom. Consequently, the kingdom of Italy was often an appendage of other larger kingdoms and empires in Europe.
Beginning in the 8th century, the King of Italy was often also the Frankish king. Later, the king of Italy became a regular title of the Holy Roman Emperor. Italy itself also became home to many Papal States, independent city states and a cultural districts during the medieval ages.
Pepin was the son of Frankish king Charlemagne. He was crowned the King of the Lombards in 781, consequently becoming the King of Italy. During his reign in Italy, the Avars were expanding their influence in the region. Pepin and Charlemagne launched a unified assault against the Avars in 791.
Although Charlemagne left the campaign quickly to deal with matters elsewhere, Pepin successfully concluded the campaign and pushed the Avars out of Italy. He also attempted to take control of Venice but failed. He died in 810 and the Italian crown passed to his son.
Louis II was crowned the King of Italy in 844, at the age of 19. At the same time, he was also crowned as the co-emperor with Emperor Lothair. Soon after his coronation, Louis sought to expand his influence towards southern Italy. For this purpose, he first reconciled with a number of dissenting dukes in the region. He then ended the might of the large Saracen army stationed in the south.
By 855, he had become the Emperor as well. He sought the help of the Byzantine Emperor to conclusively end the Saracen threat on the Italian coast and succeeded in this by 871. The Saracens returned in 871 but Louis was successful in warding off the threat once again. He died in 875 in northern Italy.
Frederick I became the King of Italy in 1155 after he had already ascended to the German throne and led a campaign into the Italian territories. The first of these campaigns was launched in 1154 whereby Frederick intended to travel all the way to the southern Italy and wrest the control away from the hands of Normans.
However, he had to face opposition as soon as he entered Italy. Overcoming this opposition through warfare and diplomacy, he reached Rome in the midst of a crisis and restored the Pope’s power in the city. The Pope, in return, crowned him the Holy Roman Emperor in June 1155. Before soon, the Papacy had aligned with the Normans in Sicily and Frederick felt the Italian territories slipping from his grasp.
During the next two decades, he had to wrest with the Papal opposition in Italy as well as frequent rebellions in Milan. The fate of Italy and the conflict between the Emperor and the Pope was finally resolved when Frederick suffered an unexpected defeat in 1175 and formally accepted Alexander III as the rightful Pope in 1176.