The golden age of Villa Arconati is interwoven with the lives of various generations of the Arconati family, which for two centuries were owners and souls of Castellazzo, previously belonging to Marchese Guido Cusani. 

Galeazzo Arconati, cousin of Cardinal Federico Borromeo, in 1610 invested his inheritance in the purchase of the property of Castellazzo, including the ”manor house”, the farm yards and the pressing house. A lover and collector of art and an architecture enthusiast – one of his positions included rector of the cathedral workshop - he made significant changes to the structure of the ”palatium”, refining the formal aspects and eliminating more rustic elements. The manor house was composed of a rectangular block with a portico and a great staircase on the ground floor and, on the first floor, a gallery and a second block facing west, towards the main road to Milan. The modifications carried out from 1619 included changes to the portico, the enlarging of the upper floors, the purchase of sculpture, classic Roman marbles, the statue of Tiberius, once known as Pompey the Great, the Atlantic Codex of Leonardo da Vinci, and fragments of the funereal monument of Gaston de Foix. It was also Galeazzo who, from 1621, having returned from a sojourn in Rome, organised the harmonisation of villa, grounds and garden, based on examples of Roman and Florentine villas, introducing the theatres and the water features inspired by the studies of Leonardo da Vinci.

It was under Galeazzo that the borgo reaches its integrated configuration with the villa, developing together with it from that moment onwards.

The project of ennoblement of the palace of Galeazzo remains essentially unchanged and unfinished for the years following his death (1648), under the direction of Count Luigi Maria Arconati, his nephew and son-in-law, who takes care of the redevelopment of the village and the construction of the covered stables, giving us a unitary space, characterized by balanced proportions and symmetries.

After the death of Luigi Maria (1671), it was his son, Giuseppe Maria Arconati, who continued Galeazzo’s plans. It was Giuseppe Maria who expanded the Villa, constructing the south-east wing, part of the splendid facade overlooking the parterre and a series of projects in the garden. The love for art and the predilections of the collector are reflected in frescoes and paintings placed in the new wing, a continuation of Galeazzo’s vision. Other examples include the reordering of the Cabinet of Gaston de Foix, which took place from 1712, and the presence of art collections, marble statues, as well as plasters, prints and drawings, until the transfer of the library on the ground floor.

In 1718 Giuseppe Antonio Arconati, Giuseppe Maria’s nephew, man of culture, admirer of theatre and protector of Carlo Goldoni, inherited the family property. He frequently visited Paris and Vienna throughout his life, where he became familiar with architectural styles from north of the Alps, and particularly the Palace of Versailles. In 1742 works to enlarge the south-west wing began, according to the designs of the architect Giovanni Ruggeri, creator of numerous milanese palaces and villas. In the garden, around the old ”flower garden”, a U-shaped courtyard was formed, facing the main avenue and the road to Milan, and the area to the south was widened and organised into parterres. In 1750, when architectural work on the house can be said to have finished, Giuseppe Antonio summoned the Galliari brothers to paint the frescoes in the Salone da parata (reception room). With the extinction of the Arconati di Castellazzo family line, from 1772 the property passed to their cousins, the Busca family, who kept the estate together. In 1850 Marchese Antonio Marco Busca carried out more important work and restructuring, including the work on the facade along with the portico and some internal decoration, such as the trompe l’oeil of the grand staircase, attributed to Giocondo Albertoli.

From the Arconati to the Busca family, in the early 1900s the Villa passed to the Marchesa Beatrice Crivelli, who we today have to thank for its conservation.

In 1907, the Villa still had some rooms intact such as the music room, the library, the yellow bedroom and the reception room. After some redecorating work carried out during the early years of the 20th century, the small portion of the Villa still inhabited was restructured in the 1970s. In 1989 all of the precious objects still held in the Villa were sold at auction.