The fortress was built in 1385 by the Marchesi Bonifacio and Antonio Lupi who in 1347 had received feudal investiture over the territory from Charles IV, power that their family continued to exercise until was abolished at the time of Napoleon. It is probable that the first fortress, with a square floor plan and four towers at the corners, took only a year to build, while the outer walls were completed in 1392. At that time, the building appeared as a powerful fortress equipped with all kinds of defensive structures against attacks from the outside. As time went by, and the Signorias became consolidated, conflicts between feudal lords gradually decreased and it was therefore possible to make the structures of the castle more genteel turning it into a more pleasant and comfortable residence, while still preserving its older parts. The castle in fact underwent considerable rebuilding especially in the 16th century, but it was only in the next century that it became a magnificent princely residence, with the appearance that it still has today. Subsequent modifications were made by Angelo Rasori from Parma and by Antonio Tomba from Piacenza, respectively in the 1700s and 1800s. The fortress, enriche over time with countless works of art and invaluable evidence of the past, has always remained the property of the Meli Lupi family.
The history of the Meli Lupi family cannot but start from the most ancient of the Lords of Soragna, Marchese Guido Lupi, who was podestā of Parma in 1202, performing important pacifying actions in neighbouring lands. In ancient times, in all likelihood, the Lupi family built the castle and numerous other small fortresses in the area: we know, in fact, that in 1318 the troops of the Podestā of Parma destroyed a small castle belonging to Albertazzo Lupi, guilty of having refused to pay a fine. Another fundamental event in the history of the family was the conversion of their properties in Soragna into a feud, by King Charles IV of Bohemia in 1347, with recognition of the title of Marchese for Ugolotto Lupi and his descendents, as well as of the right to 'mere and mixed rule and power of sword over the feud'. After long tribulations due to a dispute regarding inheritance of the family name and property, in 1530 the Emperor Charles V granted the Marchese Giampaolo Meli the right to add the name of the extinct Lupi family to his own name, as well as the privilege of including the imperial eagle insignia in the family coa of arms. One of the personages who brought most distinction and prestige to the Meli Lupi family was without a doubt Isabella Pallavicino di Cortemaggiore, wife of Giampaolo II, a lady famed above all for having obtained permission from the Duke of Ferrara to have an edition of Torquato Tasso's 'Jerusalem Delivered' printed, an edition that was revised and corrected by the author himself, while still alive. Tasso dedicated a sonnet to Lady Isabella that is still held din the library of the palace. In 1709 Giampaolo Maria succeeded in having Emperor Joseph I elevate the marquisate to a Principality of the Holy Roman Empire, with the right to mint coin. Since then the title of Prince is given to the eldest son of the family. The present Prince Diofebo, besides his work, in the agricultural area, continues activities aimed at making improvements to the tourist business of the fortress itself, and in the field of music.