The name Perast is believed to have derived from the Illyrian tribe Piruste. Above the town, there are the remains of a Roman road leading from Risan to Agruvium, thus it is possible that a minor Roman fortress castrum existed at the present-day fortress site. Within the fortress, there is the 9th-century Church of St. Cross after which the fortress was named. In the Middle Ages, Perast constituted part of the commune of Kotor, and together with Kotor, played a significant role during the Nemanjics rule over the area. In 1365, Perast was among the first towns in the Boka Kotorska to place itself under Venetian rule, retaining a certain degree of autonomy in self-government. The town obtained the status of an independent commune in 1571, and during the 17th and 18th centuries experienced the greatest development.
It seems that Perast was not completely fortified, either in the high Middle Ages or later. For centuries, people of Perast were controlling the Verige strait and the road to Kotor from the Fortress of St. Cross, the island of St. George and the fortification of Our Lady of Angels, although the lack of continuous walls encircling the town represented a great problem, which people of Perast were in vain trying to solve. The Fortress of St. Cross was constructed in the second half of the 17th century although it is possible that some parts of it are even older. It is ascertained that from the 16th century onwards the fortification system of Perast consisted of the St. Cross Fortress at the highest position in the town, a system of 10 towers placed at different locations in the town itself, as well as of fortified streets and houses. The oldest tower of Perast was mentioned in the early 16th century, while the latest one was constructed following the battle of Perast in 1654.
The data obtained over the last years based on archeological researches in Perast, provide evidence that the beginnings of the settlement can be dated into a period well before the 16th and 17th century and that a part of the present town matrix is medieval.