Region
Southeast Asia

Neighbours
A portion of Indonesia shares the island of Borneo with Malaysia and Brunei. It shares the island of New Guinea; the western section, known as Irian Jaya, is under Indonesian administration, and the eastern section is part of Papua New Guinea. The rest of the republic includes the Greater and Lesser Sunda Islands, and the Moluccas.

Area
1,904,443 square kilometres (735,310 square miles)

Size Comparison
More than five times the size of Japan

A stretch of relatively open water—consisting of the Java, Flores, and Banda seas—divides the major islands of Indonesia into two unequal strings of islands: the comparatively long, narrow islands of Sumatra, Java, Timor, and others, to the south, and Borneo, Sulawesi, the Moluccas, and New Guinea to the north.

A chain of volcanic mountains rising to heights of more than 3,805 metres (12,483 feet) extends from west to east through the southern islands from Sumatra to Timor. Mount Jaya (5,030 metres/16,502 feet), in the Sudirman Range of Irian Jaya, is the highest elevation in the republic. Each of the major northern islands has a central mountain mass, with plains along the coasts. The most extensive lowland areas are on Sumatra, Java, Borneo, and Irian Jaya. Over many centuries, periodic volcanic flows from the numerous active volcanoes have deposited rich soils on the lowlands, particularly in Java.

The climate of Indonesia is tropical, with two monsoon seasons—a wet season from November to March and a dry season from June to October. The weather is more moderate between monsoons. Many parts of the country have only slight differences in precipitation during the wet and dry seasons.

Humidity is generally high, averaging about 80 per cent annually. The daily temperature range (about 20° to 32°C/about 68° to 90°F at Jakarta) varies little from winter to summer. Rainfall in the lowlands averages about 1,780 to 3,175 millimetres (70 to 125 inches) annually and in some mountain regions reaches about 6,100 millimetres (240 inches).

Archaeological remains of Homo erectus in Indonesia reveal that these descendants of modern humans lived on the island of Java up to 1.5 million years ago and are referred to as the "Java people". Remnants of an Aboriginal culture have also been found in southern Sumatra. Many groups of people settled around the estuaries of the islands and fished the abundant inland seas. Others settled in the river valleys and grew rice. These people traded amongst themselves for a long time, but by the 1st century AD they were also engaging in overseas trading, dealing in spices and timber. Early Indonesian culture was influenced by India in the early centuries AD, when it is thought that trade between Indonesia and the Bay of Bengal began.

The country is made up of 13,677 islands and split into 27 provinces. The population of Indonesia is 209,774,138 (1997), the fourth largest of any country in the world. There are approximately 350 distinct ethnic groups, many of which have their own language and most of which have their own customs. About 45 per cent of the people are Javanese, 14 per cent Sundanese, 7.5 per cent coastal Malays, and 7.5 per cent Madurese. The remaining 26 per cent of the population is made up of other ethnic groups.

More than 60 per cent of the population lives on the "inner" islands of Java, Madura, and Bali, which together account for less than one-tenth of Indonesia's land area. For several decades the government has operated a "transmigration" policy, opening up new lands in the outer islands and providing infrastructure there for the resettlement of people from Java. Millions have been moved, successfully or otherwise, which has led to reforms in the programme. During the 1980s the number being resettled fell to less than 1 per cent of the population. Meanwhile, spontaneous migration to Java from other islands continues.

About 87 per cent of Indonesians are Muslim, making Indonesia the world’s largest Muslim population. Nine per cent are Christian—some northern areas are strongly Christian—and 2 per cent are Hindu, living mainly in Bali. There are also some Buddhists, mostly among the Chinese population. However, traditional animist beliefs, such as ancestor veneration, are as important as any of these religions in the daily life of most Indonesians. Freedom of religion is guaranteed under the constitution and religious tolerance is valued. To avoid religious conflict, the government has made it illegal to attempt to convert people from one religion to another.

The people of Java form the largest cultural group. They are predominantly Muslim and have strong social and spiritual values. They are skilled in the arts of dance, music, and drama. The commercial traders of the coastal region are mostly Muslim and have a high regard for religious learning and law. The indigenous groups of Kalimantan and Irian Jaya maintain tight kinship bonds, practise animistic religions, and have an economic and social life organized around the clan group. The people of Bali are mostly Hindu and belong to traditional kingdoms.

Indonesians celebrate the international New Year on 1 January. The birthday of the Prophet Mohammed is commemorated around February 12. Nyepí is a day of rest for the Balinese after a festival celebrating the New Year and the arrival of spring. The festival’s aim is to lure out the devils that, having been swept out of Hades following the rainy season, have gone into hiding on the island of Bali. People make elaborate offerings to them and then run through the streets, their bodies painted, bearing torches and making noise to drive them off the island.

Good Friday is a public holiday, and Easter is observed, as is Ascension, 40 days after Easter, marking the day when Jesus Christ is said to have ascended to Heaven.

Independence Day, celebrated on 17 August, is considered the most important holiday in Indonesia. Muslim holidays consist of Idul-Fitri, a three-day feast at the end of the month-long fast of Ramadan, and Idul-Adha, a three-day festival for those who are not on the pilgrimage to Mecca (Makkah) and which celebrates Abraham’s willingness to sacrifice his son at Allah’s behest.

Christmas Day (25 December) is a public holiday in Indonesia. There are also hundreds of holidays related to other regional, religious, and cultural groups