Indonesia has been shaped by long interaction between original indigenous customs and multiple foreign influences. Indonesia is central along ancient trading routes between the Far East and the Middle East, resulting in many cultural practices being strongly influenced by a multitude of religions, including Hinduism, Buddhism, Confucianism and Islam, all strong in the major trading cities. The result is a complex cultural mixture very different from the original indigenous cultures.

Examples of cultural fusion include the fusion of Islam with Hindu in Javanese Abangan belief, the fusion of Hinduism, Buddhism and animism in Bodha, and the fusion of Hinduism and animism in Kaharingan; others could be cited.

Indonesian art-forms express this cultural mix. Wayang, traditional theater-performed puppet shows, were a medium in the spread of Hinduism and Islam amongst Javan villagers. Both Javanese and Balinese dances have stories about ancient Buddhist and Hindu kingdoms, while Islamic art forms and architecture are present in Sumatra, especially in the Minangkabau and Aceh regions. Traditional art, music and sport are combined in a martial art form called Pencak Silat.

Western culture has greatly influenced Indonesia in modern entertainment such as television shows, film and music, as well as political system and issues. India has notably influenced Indonesian songs and movies. A popular type of song is the Indian-rhythmical dangdut, which is often mixed with Arab and Malay folk music.

Despite the influences of foreign culture, some remote Indonesian regions still preserve uniquely indigenous culture. Indigenous ethnic groups Mentawai, Asmat, Dani, Dayak, Toraja and many others are still practicing their ethnic rituals, customs and wearing traditional clothes