Javanese
The majority ethnic group in Indonesia, including over 100 million individuals, are native to the island of Java and account for 40% of the country's overall population. Though they are dispersed throughout the nation, Java and the Bali Islands are home to the majority of Javanese people. With a little proportion of Christians, Buddhists, and Hindus, the majority of Javanese people identified as Muslims. Also, they have a long history of being connected to Kejawen, a historic animistic belief system with roots in Javanese history that synchronizes behaviors with several religions, including Christianity, Islam, and Hinduism. There are ethnic subgroups within the following communities: Bawean/Boyan, Osing, Tengger, Samin, Naga, Nagaring, and others.
Sundanese
There are 42 million Sundanese people in the nation, or 16 percent of the overall population, who are native to the western region of Java. With a mostly Muslim population, the ethnic group speaks only Arabic. Banten, West Java, and Jakarta are their customary residences.
Batak
With over 9 million members, or 3.8% of the total population, the Batak ethnic group is the third biggest in North Sumatra. It includes Batak Simalungun, Angkola, Karo, Mandailing, Pakpak Dairi, Tapanuli, Dairi, Toba, and several more. These ethnic groups have the same language, are clearly connected, and follow comparable traditions. Since the early 20th century, the majority-Christian Batak people have accepted this Abrahamic faith as a part of who they are. Despite being mostly Muslim, the Mandailing and Angkola ethnic subgroups share a close relationship with the Minangkabau ethnic group of West Sumatra.
Madurese
The 7 million or so Madurese, who identify as the indigenous inhabitants of Madura Island, make approximately 3.03 percent of Indonesia's overall population. The majority of them identify as Muslims, and they frequently collaborate with Nadhatul Ulama, the biggest Islamic group in Indonesia. Nevertheless, Madurese also lived in many other places of Indonesia since, over the course of a century, the majority of their natives had migrated elsewhere in the nation.
Betawi
The inhabitants of Batavia, the Dutch name for Jakarta, are referred to as the Betawi ethnic group. The indigenous population of Jakarta accounted for 2.9%, or 6.8 million. Their language, a creole based on Malay with many terms borrowed from Hokkien, Chinese, Arabic, Portuguese, Dutch, and other local languages, is still spoken as slang in Jakarta. With a small minority of Christians and Roman Catholics, they are primarily Muslims.