The Fieschi were a noble merchant family from Genoa, Italy, from whom descend the Fieschi Ravaschieri Princes of Belmonte.The Fieschi family exercised great influence in the Guelf (papal party) politics in medieval Italy. They had close ties with the Angevin kings of Sicily. Later they also established links with French kings. The Fieschi family produced two popes and 72 cardinals.
They held the fief of Lavagna under the Holy Roman Emperors. As Counts of Lavagna the Fieschi represented the Emperor of the West in Liguria from the earliest years of the 11th century. In 1010 the investiture of the Fieschi took place at Genoa: the family were created Counts of Lavagna and Imperial Vicars General (i.e. Viceroys) of the whole of Tuscany and of the coast of Genoa. In the words of Henry the Holy, King of Italy since 1004 and Holy Roman Emperor from 1014 and the last of the Ottonian dynasty, 'Ordiniamo il predominato Fieschi vicario generale di essa città con ampio potere.' ('We appoint the pre-eminent Fieschi to be Vicars General of this city-state with broad powers').
The Imperial Houses of Hohenstaufen, Luxembourg and later Habsburg each in turn confirmed the Counts in the rank of Count Palatine.
Males of the Fieschi— all of them styled Conte di Lavagna— played major roles as Guelph partisans in the governance and military history of medieval Genoa, ever in conflict with the Republic and always retaining their connection with their holdings here.
In 1138, in an agreement between the Fieschi and the commune of Genoa, the Fieschi agreed to spend part of the year in the city. They earned great riches from trading and financial activities, and later developed in numerous different branches. Apart from Liguria, they possessed fiefs in Piedmont, Lombardy, Umbria and in the Kingdom of Naples.