After the battle of Anghiari, in 1440—which stopped the expansion of the Milanese patrician family of the Visconti towards Central Italy—the borders between the Papal State and the Florentine Republic were set in the Upper Tiber Valley. The small town of San Giustino became a border post, and its medieval fort, which was owned at the time by the Dotti family of Sansepolcro—a Ghibelline family [2]—becomes a strategic military outpost for the defense of the territory of the larger town of Città di Castello.

The ownership of this fort—assaulted, set on fire, and destroyed several times—shifts to Niccolò di Manno Bufalini, a family of the opposite faction [3] from Città di Castello, between 1487 and 1492. Manno Bufalini, following the project of the Roman architect Mariano Savelli and the indications of Giovanni and Camillo Vitelli—two men of arms and experts in military architecture—transforms the small fort into a larger fortress.

Niccolò di Manno Bufalini, who was a lawyer of the Consistory Court "in utroque iure" [4] and a Palatine Count at the service of the popes, completes the construction work around 1500 with the help of Lombard Master craftsmen from the cities of Città di Castello and Citerna. The New fortress has a quadrangular plan, with its four angular towers it presents all the characteristics of the architecture of military construction during the transitional period between the middle-age construction defense system of machicolation—like battlements with corbelled arches—and the modern fortifications apt to confront cannonballs and bombards in the age of gunpowder.

In 1530, Abbott Ventura and his brother Giulio Bufalini (heirs of Manno) began to transform the fortress into a fortified palace, with large loggias and various rooms, all distributed along and around the internal court that, at that point, had two porticos. This transformation was based on the design of the architect Giovanni d'Alessio, called Nanni Unghero (Florence 1490 approx. - 1546), who was part of the Sangallo entourage and in the service of Cosimo I de Medici, Grand Duke of Tuscany.

The construction work is completed around 1560, right before pope Pious IV concedes the investiture of the feudal county of San Giustino to Giulio Bufalini and his son Octavio in 1563, when the latter marries the Milanese princess and niece of Saint Carlo Borromeo, Dorothea Ferreri.

For the interior decoration, the Bufalini brothers call the artist Cristofano Gherardi (San Sepolcro c.1508-1556). An imaginative and refined painter from a mannerist background, he paints—between 1542 and 1552—mythological scenes enriched by grotesque decorations in the Main Tower, in The Room of the Gods and in The Room of Apollo. In The Room of the facts of the Romans, on the first floor of the building, the painter sets episodes of the glorious history of Rome framed by refined plaster decoration with the archaeological taste taken from Nero's Domus Aurea. In The Room of Prometheus, on the ground level, he depicts the Myths of Prometheus and Pandora.

During the last ten years of the seventeenth century and the beginning of the eighteenth century, with the taking over of the project by Giovanni Ventura Borghesi (1640-1708), architect and painter from Città di Castello, the Bufalini residence, already the center of a large farm, is transformed into a pleasant countryside Villa, with a replanted "Italian" garden, which is irrigated by the water of the nearby river Vertola through an underground conduct connected to a water channel called "Reglia" [5]. In the Castle's garden it is possible to find a large variety of fruits, citruses with a lemon-house, officinal herbs, rare flowers, a vegetable garden, a small grove area called "Ragnaia"—in Italian this means ‘the spider nets’ to capture birds by positioning nets betweens trees—and a labyrinth that was planted in 1692.

On the occasion of the marriage of the first-born marquis Filippo I Bufalini with the marquise Anna Maria di Sorbello (1700-1701) many works of art of fine late baroque taste were executed, such as the monumental fresco in The Throne Room celebrating Bufalini's acquisition of the noble title of marquis, or the Portraits Gallery, a delicious antechamber of the private apartment of Filippo I located in the Main Tower. Giulio III and Niccolò II—brothers of Filippo I—also commissioned some pictorial and decorative cycles, such as the monumental canvasses of Mattia Battini in The Throne Room and The Room of the Plastered Decorations with the Stories of the Strong Women of the Past.

In 1789, a violent earthquake provokes the collapse of the ancient Bell Tower and of the upper floors of the entire building—the mezzanine floor, the apartment and dovecote of the Main Tower and the armory. In order to repair the severe damages, Marquis Filippo II obtained permission from the Pope to sell off a good part of the works of art and family furniture that remained under the control of the Fideicommissars [6], causing the dispersion of even great masterpieces in the antiquarian market.

Notwithstanding this dispersion, Castello Bufalini remains one of the few historical manors that still conserves a large part of its furniture and fittings, a heritage consisting of a collection of archaeological pieces, paintings, furniture, ancient fabric, various ornaments, ceramics and crystal-ware evoking the atmosphere in which the ancient Umbrian family used to live. An atmosphere that includes all the family members who lived here and were successful in the military, ecclesiastical, literary and juridical fields and who worked in the service of the Papal State, the Medici, Farnese, Colonna and Este families and even in the service of the Royal families of Spain, England and above all France, where they were favored by their family relationships with Cardinal Jules Mazarin. This collection also includes interesting pieces of art from the collection of the art lover, Cardinal Giovanni Ottavio Bufalini (1709-1782), who was bishop of Ancona and a refined collector. These precious pieces had already been kept in the family Gallery of Palazzo Bufalini, in Città di Castello, and were moved to the San Giustino premises at the beginning of the twentieth century.

Part of the uniqueness of Castello Bufalini is the presence of Family Archives, one of the most important private archives in Italy, while its garden that includes the labyrinth is a rare example of an “Italian” garden in Umbria.

The current state of the restoration work allows the opening to the public of the Ground Floor of the building, the late Renaissance Loggia on the First Floor and The Room of the Gods in the Main Tower mezzanine, in which there are Gherardi's frescos and the Italian garden. The visitor is offered the opportunity to take a trip through the past in a building in which works of art are exhibited along the way, not in chronological order, but according to the tastes and interests of the old owners. The intention of the exhibition is to maintain, as much as possible, the atmosphere of an environment where an ancient Umbrian family lived, which is full of heterogeneous significance. The history of the Bufalini family itself, reconstructed through documents from the Archives and characterized by the images visitors can capture in some of the family portraits along the way, is the guiding thread that accompanies visitors along the museum's pathway.

For the opening of the entire Bufalini complex as a Museum to the public, further funds are needed together with a general plan for its use, which includes the upper floor—with the Gherardi pictorial cycles, the Cardinal Giovanni Ottavio collection and the nineteenth century works of art. Furthermore, the plan foresees the integration of the precious Wine Cellar—where barrels and equipment for the preservation of wine are still kept—into the Museum.