The etymological origins point to a Roman encampment near the river Belbo (Castrum novum ad Belbum), however the most credible theory is that the fortress was constructed around the year 1000 to defend the castle of Incisa which was increasing in importance after becoming an independent marquisate. In 1499 Castelnuovo was attacked and pillaged by French troops led by Gian Giacomo Trivulzio. After being acquired by the Trotti family the estate then changed hands numerous times.

The conformation of the territory led to the development of a prevalently agricultural economy, with viticulture of prime importance. The physical and chemical characteristics of the land and the moderately hot, humid climate, make the soil difficult to work and dry in the summer, more suited to viticulture than herbaceous cultivations.

ARCHEOLOGICAL SITE

The parish church, around which the entire inhabited area extends, was built during the baroque era. The construction of the town hall was first seriously considered around 1850. The first notice of construction carries the date of 24 June 1857. Shortly after completion, the structure was found insufficient to hold the offices, council meeting room and school. The elegant construction in brick presently in use dates from 1887.