Palazzo Mazzancolli is considered to be one of the most important examples of medieval architecture in Terni, even if, in fact, it dates back to the beginning of the Renaissance period. It was built towards the middle of the 1400s. The Mazzancolli family wanted a sign of their power, of which they had in abundance. Ludovico Mazzancolli was Bishop of Terni from 1406 to 1458, his brother Ettore was Notary of the town Chamberlain and Prior. Giovanni, one of Ettore's three children, was the most powerful of the family: judge of civil and criminal cases in Marche: curate to Sigismondo Malatesta and Mayor of the city of Rimini: governor of Città di Castello and then Terracina:auditor of Apostolic cases, very close to Pope Pius ll, refined diplomat and unconventional politician.
Giovanni wanted the mansion to be erected, built upon the foundations of two existing towers. The family coat of arms was "melted" into the facade: an arm holding a mace leaning on a neck. The work continued for eight years; but in 1458 the building was finished, and in that year exactly, Ludovico died, receiving, in the cathedral of Santa Maria Assunta (now Cathedral of Terni), a funeral worthy of a member of a family, which held in their hands most of the control levers in Terni. The following year, in 1459, the lustre and the power of the Mazzancolli family was recognized by the Pope, who dwelled during a journey to Mantova.
The Mazzancolli occupied the building only for about sixty years.
Rising to fame rapidly, the family declined just as rapidly. At the beginning of the 1600s they left Terni. The mansion was abandoned for nearly a century then hosted a spinning mill. Subsequently, it hosted the Monte di Pietà pawnshop and,more recently, the Fascist Party and the Police Headquarters. Now, restored, it hosts the State Archives.
Every time there was a change in its usage, the building underwent restoration work and subsequent changes. Of particular interest is the small interior courtyard, dominated by an elegant three- tiered porch, the same that might have been what today is a somewhat heavy staircase, which was once part of the first floor first court and was affected by the fact that it was completely demolished and then rebuilt during the reconstruction work of 1926, when the "Mazzancolli" was used by the fascist federation. The works, designed by Gaetano Coppoli were also influenced by the architectural "trends" of the time which can be notednot only by the staircase, but also in other parts of the building.