A Medieval town of traditional structure which has maintained its appearance as it was in the early 10th century, the Old Town of Castell'Arquato is a high rock which in other times was strategically important for dominating the valley, now surrounded by the village.
Castell'Arquato is also in the area of the Colli Piacentini (Piacenza Hills), an important area for wine production. The most important wines produced in the Colli Piancentini are Gutturnio, Bonarda, Ortrugo, Malvasia, and Monterosso Val d'Arda.
The first historical news concerning Castell’Arquato (known as la Pieve) appear in the 8th century. Castell'Arquato seems to have been constructed by a "noble and powerful Domini named Magno." Magno built the squared based castle and a church "In honor Mater Dei" (756-758).
At that time Castell’Arquato had a military (Castrum) and an agricultural organisation (Curtis), the Justice Administration (Curia) and the Religious Administration (Pieve).
Before dying in 789 Magno gave the town, the church of Santa Maria and its goods to the bishop of Piacenza, and Castell’Arquato acquired an important freedom as a Pieve. With Magno's donation, Castell’Arquato was now under the dominion of the Bishop of Piacenza.
There is proof that in the last decades of the first millennium that the burg of Castell'Arquato was bustling with vitality. The Bishop had the right of direct taxation (fodro) throughout the territory of Castell'Arquato on all the men, nobiles, burgenses, lords with houses and lands in the area and on the clerics of Santa Maria.
From 1204 to 1207 the Bishop of Piacenza Grimerio chose Castell’Arquato as his home. The burg became even more independent from Piacenza. The grant of an autonomous government became official in the summer of 1220.
The first document in the historical archive of Castell'Arquato is from 10 August 1220 when the Bishop Vicedomio gave his land in the burg and the territory in Emphyteusis (a form of fiefdom) to the "burg and to the homines" of Castell’Arquato for 700 piacentian lire. For 200 lire and a small annual fee he gives also “in perpetual investiture all jurisdictions, honors and tithes" of Castell’Arquato, Lusurasco, San Lorenzo and Vernasca.
Castell’Arquato was at the time ruled by a Podestà chosen by the Comune of Piacenza from among the most renowned members of the Piacenza's families, serving for a term of three years. The Podestà had civil, political and judicial functions.
The Podestà's rule ended in 1290 when Alberto Scotti, backed by the guelph faction, the merchant class and the artisanal corporations, became lord of Piacenza. Castell’Arquato then also became a Signoria on its own right. Alberto Scotti allied himself to the Visconti family and extended his dominion to the territory of Piacenza. In Castell’Arquato he put the podestà Tedesio de’ Spectinis in charge. The alliance with the Visconti ended in 1302 when the son of Matteo Visconti, Galeazzo I Visconti, married Beatrice d’Este and shifted the weight of the alliances, starting a period of conflict that brought the Scotti to Milan.
Under Scotti dominion, Castell’Arquato acquired political prestige and many of the buildings that can be still be seen today, like the Palazzo del Podestà (Podestà's Palace) and the Palazzo di Giustizia (Court of Justice), nucleus of what is today the Palazzo del Duca (Ducal Palace).
In 1304 Alberto Scotti was banished from Castell’Arquato by the city of Piacenza, but came back three years later, in 1307. After the arrival of Henry VII in 1310 Alberto Scotti ruled the burg, until 1316 when Galeazzo I Visconti besieged Castell’Arquato, which yielded after one year.
Galeazzo Visconti allowed the burg “special rights”: the ability to juridically emancipate itself from Piacenza and to write laws of its own, the basis of the 15th century statutes. The rule of the Visconti lasted until 1450.
In 1324 Castell’Arquato was given to the municipality of Piacenza, itself under the dominion of the Church, which governed the burg for twelve years. Piacenza went back to the Visconti in 1336 with Azzone Visconti, who favored the burg's autonomy from Piacenza, appointing a trusted podestà, Galvagno de’ Comini, and facilitating the fortification of this strategically and militarily important area. He died at the age of 37 years. His successor, Luchino Visconti was responsible for the construction of the Rocca (starting in 1342), promoted by the municipality of Piacenza.
In 1403 Gian Galeazzo Visconti gave Borromeo de’ Borromei and his descendants feudal powers over Castell’Arquato, with the related fiscal revenues. Threatened by the powerful family of the Arcilli from Firenzuola, they gave back their rights to the people of Arquato, who gave them to Filippo Maria Visconti, Duke of Milano. From 1416 to 1470 the burg was called Castel Visconti.
In 1438 Filippo Maria Visconti offered the fief to the military leader Niccolò Piccinino, under whose government the Municipal Statutes were promulgated, the Statuta et Decreta Terrae Castri Arquati. From Niccolò the burg was passed to his sons Francesco and Jacopo. The dark period of the Visconti dominion ended with the heirless death of Filippo Maria Visconti. His son in law Francesco I Sforza turned towards Milan, and was in 1447 also declared lord ofPiacenza and its area. The dominion of the Sforza ended in 1707.
In 1541 Pope Paolo III Farnese declared the independence of the burg, having already initiated the process in 1538. He also visited the Burg in the spring of 1543 when he was acclaimed by the population, grateful because the independence from Piacenza also meant economical relief.
The rule by the Sforzas went on until 1707, when the territory of Castell'Arquato became part of the Duchy of Parma and Piacenza under the Farnese and Borboni. Until 1860 the Duchy of Parma and Piacenza was part of the estates of Maria Luisa d’Austria, and it is in this date that it became part of the state of the Savoia.
The current coat of arms reflects these changes, featuring the castle alongside the symbols of Piacenza (red castra of Sant'Antonino), the Farnese (golden fleur de lis); the Scotti (6-pointed gold stars) and the Sforza (golden lions).