Founded in 1103 by Seminio of the counts of Collazzone, it was fortified in 1322 with the construction of a tower and massive defensive walls. In 1363 it was attacked and conquered by the Compagnia del Cappelletto. This company, after conquering San Gemini and Simigni, obtained from the town of Todi 1,000 florins as a payment to leave these places. The company kept its word, but created a small feud around the Torreuccia Castel, between Gualdo Cattaneo and Bastardo. This company was formed by descendants of Italian nobility in search of adventure and glory. In December 1363, just after being released from Siena prison, Nicolò da Montefeltro tried to reach his companions who were camped at Simigni, but he was captured and imprisoned by the people of Todi. Simigni came under the dominion of the Trinci family in 1389, under Braccio Fortebracci in 1410, then again under the Trinci family and from them passed to the Attis. Many estates, at that particular time in history, were passed back and forth between the Trinci and the Fortebracci families. In 1435 Corrado XV Trinci returned Simigni to the governor of Perugia, Monsignor Alberto Alberti. The castle after a feoffment to the Atti, passed under the jurisdiction of the Cistercian abbey of Chiaravalle and later, set up as a county, was governed by Count Frederick of Simigni. In 1645 it was regained by the Oddi family in Todi, also owners of the Atti palace. At the beginning of the 1600s the prior of Todi, Benigno Degli Oddi, made restorations and embellishments of great significance to the city. Today the castle belongs to the Bonadies family of Rome.