Prehistoric Indonesia

Prehistoric Indonesia is a prehistoric period in the Indonesian archipelago that spanned from the period to about the 4th century CE when the Kutai people produced the earliest known stone inscriptions in Indonesia. Unlike the clear distinction between prehistoric and historical periods in Europe and the Middle East, the division is muddled in Indonesia. This is mostly because Indonesia's geographical conditions as a vast archipelago caused some parts — especially the interiors of distant islands — to be virtually isolated from the rest of the world. West Java and coastal Eastern Borneo, for example, began their historical periods in the early 4th century, but megalithic culture still flourished and script was unknown in the rest of Indonesia, including in Nias, Batak, and Toraja. The Papuans on the Indonesian part of New Guinea island lived virtually in the stone age until their first contacts with modern world in early 20th century. Even today living megalithic traditions still can be found on the island of Sumba and Nias.

Geologically, the area of modern Indonesia appeared from under the Southeast Asian seas as the result of the Indian and Australian plates colliding and slipping under the Sunda Plate, sometime in the early Cenozoic era around 63 million years ago. This tectonic collision created Sunda volcanic Arc that has produced chains of islands of Sumatra, Java and the Lesser Sunda Islands. The active volcanic arc creating supervolcano that today become Lake Toba in Sumatra. The massive eruption of Toba supervolcano that occurred some time between 69,000 and 77,000 years ago instigated the Toba catastrophe theory, a global volcanic winter that caused a bottleneck in human evolution. Other notable volcanoes in Sunda Arc are Mount Tambora and Krakatau. The region is known for its instability due to volcano formations and other volcanic and tectonic activities as well as climate changes; resulted in lowlands drowned occasionally under shallow seas, the formation of islands, the connection and disconnection of islands through narrow land-bridges, etc.

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