On September 8, 896, Countess Ingelrada donated the town of Modigliana to her son Pietro, deacon of Ravenna. In 925, the castle of Modigliana fell under the control of Ingelrada II, daughter of Duke Martin of Ravenna. In the 10th century, Guido, founder of the Guidi counts, was made Count Palatine by Emperor Otto I of Saxony and received from him the county of Modigliana in Romagna.
On September 28, 1164, Emperor Frederick I Barbarossa confirmed possession of the castle of Modigliana to Guido Guerra. In 1166, the castle of Modigliana hosted Emperor Frederick I Barbarossa and the empress, who gave birth to a son named Corrado there. On May 25, 1191, Emperor Henry VI of Swabia confirmed possession of the castle of Modigliana to the Guidi counts. On November 29, 1220, Emperor Frederick II confirmed possession of the castle of Modigliana to the Guidi counts. On March 21, 1230, following the division of the Guidi counts' patrimony, Modigliana was awarded to Guido and Tegrimo.
In 1278, Modigliana was besieged by the Florentines. On June 14, 1362, Fiore di Guido di Domestico dei Conti Guidi da Modigliana surrendered to Florence along with his castles, including Modigliana. On August 7, 1377, Modigliana submitted to Florence, and following this event, the latter imposed the construction of a third wall (in addition to the first, not far from the fortress, and the second, intermediate one), several miles long and featuring 12 towers, terminating in an imposing gate, the "Tribuna," overlooking the Tramazzo River. In 1415, Modigliana was a first-class castle in the Florentine district. In 1440, Modigliana Castle was captured by the troops of Guidantonio Manfredi, who obtained a donation from the Visconti family.
In 1445, Florence regained possession of Modigliana Castle. In 1502, Vitellozzo Vitelli conquered and plundered Modigliana Castle. Subsequently, the loss of its military function, the earthquake of 1661, followed by further strong tremors in 1773, led to its abandonment. In 1918, part of the circular keep collapsed, resulting in its vertical section.
Source: Wikipedia