The town's name has uncertain origins: some sources attribute it to person's name of Germanic origin, "Penno". A small town in the province of Asti, it is situated on a hill on the right bank of the Rio Grana, bordering with the territory of Alexandria.
It is believed that in the Middle Ages, Penango was just a small district, part of the "iudiciaria torrenti" which lost its autonomy in the X century when it was divided between the citizen committees of Asti, Vercelli and Turin. In the next century the area was claimed by the Aleramici and the Bishops of Asti and Vercelli. Subsequently it became, with Cioccaro, a possession of the Lords of Olivola. In the XIV century the territories were annexed to the nearby towns and became part of the Cantons of Moncalvo. Proclaimed fief by Duke Carlo Gonzaga, Penango was ceded to the Marquis Jean Galbert de Campistron, secretary of the King of France. The new community was founded in 1704 with the division of the Canton of Moncalvo into three smaller ones: Patro, Santa Maria e Penango. From this period onwards, in the Southern area of the District of Moncalvo, several diverse and heterogeneous settlements were founded. In 1717 all the rights were sold to the Marquis Francesco Mossi of Morano. It then belonged to the Duchy of Monferrato and was annexed in 1708 to states of the Savoy, becoming part of the province of Casale. This situation lasted until the fall of the old regime. Under the French, it was submitted to Alexandria in the department of Tanaro before and Marengo later. In 1814 Penango became part of the reconstituted province of Casale, till in 1859 it returned under the rule of the province of Alessandria.

Not to miss:

- the Parish Church of San Grato, built in the late XVII century, and rebuilt and enlarged around the middle of next century in Baroque style, probably designed by Magnocavallo. It was restored and decorated in 1897 by the Morgari. Inside are preserved two paintings of the artist Caccia, a wooden choir, brought here from the Church of Santa Maria of Piazza di Casale, the organ gallery and the confessional, that date from the second half of the XVIII century, art works of the craftsman in ebony, Allemano;
- the medieval Church of Saints Ippolito and Cassiano;
- the Parish Church of San Vittore, located in the district of Cioccaro, was erected where once stood a previous Romanesque church of which remain only some arches and a window. It features a single nave and houses two paintings of the artist Caccia.