Since the ancient years of the Greek culture the historical continuity of the region is uninterrupted, despite the conquerors and invaders that have passed over time. There is also a special bond with the mainland coats opposite, where important centers of the Greek ancient culture have flourished, such as those in modern Albania (Ogchismos ,Vouthroto and other) or in Epirus, whose inhabitants are supposed to have settled in Kassiopi.
According to another version ( A. Moustoxidis) inhabitants of the town Kassiopi at the opposite mainland coasts are said to be the first to have settled in Kassiopi. According to another version the town was built by the King Pyrrhus of Epirys. King Pyrrhus got the island as dowry for this marriage with Lanassa, daughter of King Agathocles of Syracuse. Pyrrhus decided to increase the population of the island in order to protect the opposite coasts during the wars with Italy and brought therefore people from Epirus to settle especially in its nothern part. There are reports dated back to 500BC on the Epirot settlers of Kassiopi.
According to one version, the name Kassiopi derives from the know constellation Cassiopeia in the northern hemisphere having the form of a W. The myth says that Cassiopeia was the wife of King Cepheus of Ethiopia and mother of Andromeda. Cassiopeia was proud of her beauty and compared herself to Nereids. This made Poseidon, god of the sea, furious. He sent a sea monster, named, Cetus, to the coasts of Ethiopia in order to exterminate the people of the country. Cepheus consulted an oracle who told him to chain his daughter Andromeda, on a rock and give her to the
monster as a sacrifice to Poseidon. When King Perseus saw Adromeda chained on the rock, he amazed by her beauty, killed the monster and set her free. When Cassiopeia died became a constellation the Great Bear.
Another version says that the name derives from the word "Κάσσιος"(Cassius) and
"οπή" (meaning ''hole'') referring to the source in the area of the castle. The place, where today stands the church of Holy Mary (Panagia Kassopitra), used to be a temple devoded to Zeus Cassius. Another similar temple used to stand in Kassiopi in Epirus.
Due to its location Kassiopi flourished from the very beginning. This is indicated also by the presence of a mint. It continued to develop also during the Roman occupation and later in the Byzantine years.The castle of Kassiopi signifies the ancient history of Corfu. It was built by the
Romans (there could have been another building in its place earlier). From the castle one could control the strategic passage between Kassiopi and Vouthroto.
It has the typical defence characteristics, such as height in order to increase the speed and the destroying power of the shoots and vertical out side walls in order to hinder climbing of possible conquerors.
In 577 AD the Goths destroyed it. Its decline begins basically since the 11th century AD with the decline of the Byzantine empire. In 1081 Robert Guizcard, a Norman leader, occupies Kassiopi. In the following years the Crusaders plunder Kassiopi, as well as the whole island. In 1386 the
castle of Kassiopi is occupied by Angevins, who fought against Venetians prevailed, they destroyed the castle completely. The town remained unprotected and lost its significance. 100 years later Venetians rebuilt it until the Turks devastated it and destroyed the church of Holy Mary in 1537. In 1571 , after another invasion of the Turks, everything was burnt and most of the population was exterminated. At the same time the big forest that extended to the eastern side of the mountain from Spartylas to Sinies and Kassiopi was also burnt.
The invasion of the Turks is supposed to have led the Venetian Senate to decide to issue a decree in 1623 providing that every man who owned land without olive trees should plant 8 trees in every one staro (Venetian unit of measurment) land. Thus,the Corfiot olive grove was created. This measure reinforced the area of Sinies economically. Over years Kassiopi became a picturesque fish village. Since 1970 it has become a popular destination for the tourist in Corfu and its economy has improved significantly.