This famous Guelph family from the castle of Verrucchio, which lies between Rimini and S.Marino, fell heir to the fortress of Gradara, in the territory of Pesaro, and by degrees extended its power in the direction of Ancona.

In 1285 Gianciotto Malatesta became lord of Pesaro, and on his death, in 1304, his brother Pandolfo inherited his domain.
From that time the Malatesta, lords of nearby Rimini, controlled not only Pesaro, but a large part of the March which they appropriated to themselves when the papacy was removed to Avignon.

They secured themselves in the possession of Rimini, Pesaro, Fano, and Fossombrone by an agreement made during the life of the famous Gil d'Albornoz, confirming them in their position there as vicars of the Church.

A branch of this house resided in Pesaro until the time of Galeazzo Malatesta.

Threatened by his kinsman Sigismondo, the tyrant of Rimini, and unable to hold Pesaro against his attack, he sold the city in 1445 for twenty thousand gold florins to Count Francesco Sforza, and the latter gave it as a fief to his brother Alessandro, the husband of a niece of Galeazzo.