The first residents of the archipelago belonged to Asian and Oceanian civilizations. They had a relatively developed economy and culture that soon came under Chinese and Indian influence.
Among the small domains, the kingdom of Sri Vidaya (Sumatra) stood out, which had its heyday between the ss. VII and IX, when it suffered the Hindu invasion, and the kingdom of Majaram (central Java), which ended in the 9th century. During this period, a national culture flourished with features different from those from India.
In the days of the Kadiri dynasty (1049 – 1222) solid commercial agreements were established with the Arabs, with whom they exchanged spices for fabrics and metals. After the Singmasari Dynasty (1222 – 92, the cult of Shiva-Buddha), Java was united in a kingdom that included Madura, Bali and Sunda.
Javanese expansion continued during the 14th century, bringing together Sumatra, part of Borneo, Celebes, the Moluccas, and the Malay Peninsula to Kedah. The conversion to Islamism began in the 13th century ; in 1520 the Muslims took over the Javanese Empire and confined Hindu beliefs to the island of Bali.
In the 16th century, the Spanish and Portuguese entered into trade agreements with the Islamized Indonesian kingdoms. From 1596 and for several centuries, the Dutch seized a monopoly on trade, relying on a powerful navy and creating mercantile companies.
According to the national census of 2000, the Indonesian population totals more than 206 million people, and by the mid 2000s, the Central Statistics Bureau and Statistics Indonesia Indonesia estimated a population of 222 million.
By 2009, the country’s population reached more than 229,500,000. 130 million people live on the island of Java, the most populous island in the world.
Despite a fairly effective family planning program that has been in place since the 1960s, the population is expected to reach more than 315 million by 2035, based on the current annual growth rate of 1.25%.
Most Indonesians are descendants of Austronesian-speaking people, whose languages come from Proto-Austronesian (PAn), indicating that they likely originated in Taiwan. The next largest population group in the country are the Melanesians, who live in the eastern part of Indonesia.
Nearly 300 native ethnic groups coexist in the country, with more than 700 languages and dialects. The largest ethnic group is the Javanese, who represent 42% of the population and are the dominant group from a political and cultural point of view.
Although religious freedom is stipulated in the Indonesian Constitution, the government officially recognizes only six religions: Islam, Protestantism, the Catholic Church, Hinduism, Buddhism, and Confucianism. Although it is not an Islamic state, Indonesia is the nation with the most Muslims in the world, with about 86.1% of the population being Muslim, according to the 2000 national census.
Of the rest of the population, 8.7% are Christian, 3% are Hindus and 1.8% are Buddhist or of other religions. Most of the Hindus in Indonesia are Balinese, while the majority of Buddhists in Indonesia are of Chinese origin.
Although they are currently minority religions, Hinduism and Buddhism had a great influence on Indonesian culture. In the 13th century, the Indonesians of North Sumatra were the first to adopt Islam, thanks to the influence of merchants, and during the 16th century it became the dominant religion of the country.
According to andyeducation, Catholicism was brought to Indonesia by Portuguese colonizers and missionaries, and Protestant denominations are largely the result of efforts by Dutch groups of Calvinists and Lutherans to Christianize the population during the country’s colonial period.
A large part of Indonesians – like the Javanese Abangan, Balinese Hindus, and Dayak Christians – practice a less orthodox and syncretic form of their religion, which is based on local customs and beliefs.
Biota and environment
The size, tropical climate and geography of the archipelago make Indonesia the second country with the highest level of biodiversity in the world (after Brazil), and its flora and fauna is a mixture of species from Asia and Australasia.
Once linked to the Asian mainland, the islands of Sumatra, Java, Borneo and Bali, have a great variety of Asian fauna. Large species such as the tiger, rhino, orangutan, elephant and leopard were once abundant as far east as Bali, but the number of individuals and their distribution have been drastically reduced. Forests cover about 60% of the country.
In Sumatra and Kalimantan, Asian plant species predominate. However, the smaller and more densely populated forests on the island of Java have been largely wiped out due to human activities.
For a long time, the Celebes Islands, Nusa Tenggara and Maluku, were separated from the continental landmass, for which they have developed their own flora and fauna unique in the world.  Papua was part of the Australian land mass and is home to flora and fauna closely related to that of Australia.