During its existence as a greece polis, Issa was very important destination on the east coast of the Adriatic sea. Also some historians claim that Issa was the main center of the greece colonisation on the Adriatic sea. Issa was developing itself as an independant polis and in addition to that, Issa also developed its own religion and cults. Despite of the arrival of the greek colonists, an island was inhabited by their Ilirian natives which undoubtedly have had the main influence in creating their religious image, and by all that they were showing how Issa was a kind of assimilation of greek arrivals and illirian natives. To testify on that behaf, there is a ritual of quoting genealogical relations to three generations backwards of the deceased person, which was not present in greek rituals, but the Issa inhabitants such as cult od Joni Illirian wich was a historical persona whom only Issa inhabitants had as their protector.