The earliest record of the toponym Tromellum dates from 1250, when it was mentioned on the list of estates under the dominion of Pavia. In the following centuries it was property of the Beccaria family, until 1474, when its last heirless member, Agostino, died. Galeazzo Maria Sforza enfeoffed his cantor Cordier with Tromello. Its owners also include Carlo of Capo Silvo, in 1478, and later his son-in-law, Leonardo of Comite. In 1535, the estate became subjected to Count Massimiliano Stampa, after whose death it was inherited by his brother, Ermes, and subsequentlz by the heirs (the Marquises of Soncino), until 1797, when feudalism was abolished.