The first Pallavicino fief was created by Oberto II, who received it from Holy Roman Emperor Frederick Barbarossa in 1162.

A number of lines are descended from Guglielmo (died 1217), possessor of a series of fiefs between Parma and Piacenza.

Through the descendants of Guy and his brother Rubino, sons of Guglielmo, a branch of the family rose to prominence in the Latin Empire founded after the Fourth Crusade in 1204.

They grew in riches and, after 1224, became also the most powerful family in the former Kingdom of Thessalonica (northern Greece).

The Pallavicini were related to the De la Roche family then ruling in Athens.