Indonesia is a nation of over 13,000 islands. Largely for this reason, it encompasses a very diverse range of cultures and languages.Currently around 90% of the population identifies with Islam, but the practice of this religion varies widely in different locales.An important term to know when discussing ritual in Indonesia is “adat.”Here is the religious demography (= statistics of the religious characteristics of the population) of Indonesia. “Modernist Islam” means Islam that is more in line with the rules of international Islam (as found in the Middle East). “Traditional Islam” in this context means Islam that is more thoroughly mixed with non-Islamic local traditions (adat). In fact, we can also find local adat in the so-called modernist Islamic areas.Adat basically means “tradition” in many Indonesian languages.In recent centuries, the coming of Islam has added a veneer of commonality across the archipelago (= islands), as each locale adapted itself to Islamic practices.However, these local cultures also retained many of their own ancestral practices, and some may have even continued to give precedence to certain pre-Islamic adat rituals over Islam.In many areas, Hindu-Buddhist influence prior to the coming of Islam had added another set of ritual practices.In this way, Indonesia became a land of diverse rituals from different times in history, often coexisting as distinct practices and also mixing into new local forms.