It was the Spaniard Ynigo Ortiz de Retes who, in 1545, gave the name Nueva Guinea to a strip of land on the north coast of the world's second largest island (after Greenland), which is now half Indonesian, half Papua New Guinean territory.

Irian Jaya, the western half of the island, is Indonesia's biggest province of about 410,000 square kilometers, representing almost 21 percent of the country's total land area. More than 75 percent of the land is covered by dense tropical forest, with only about 1.5 million people, with an average population density of 2.8 persons per square kilometer, the lowest in Indonesia. Jayapura, the neat provincial capital on a hillside overlooking the bay, is 3,520 kilometers away from Jakarta.

Irian Jaya is a land of exceptional natural grandeur. Its jungles are among the wildest, most impenetrable in the world. Eternal snow caps mountain ridges more than 5,000 meters high, with walls that plunge hundreds of meters down onto floors filled with small glacier lakes. It has scenic beaches in aboundance as well as immense stretches of marshlands. Cool grassy meadows lie at the foot of the fowering mountains. Rivers cut through dark forest until their sluggish, crocodile infested mounths disgorge the water into the sea.

The highest peak of the central mountain range is Puncak Jayawijaya (5,500 meters). Second and third are Gunung Triloka (5,160 meters) and Gunung Yamin (5,100 meters), respectively. The biggest lake is Paniai, followed in order of declining size by the lakes Ronbenbai and Sentani, both in the vicinity of Jayapura, and Anggigita near Manokwari. On the basis of physically features and differences in language, customs, artistic expression and other aspects of culture, the indigenous people of Irian Jaya are distinguished into about 250 sub-groups, although they all belong to the Melanesian race, and are related to the people inhabiting the islands along the southern rim of the Pacific. The Negritos are believed to have settled on the island first, probably some 30,000 years ago, followed by the Melanesians. The people of the central highlands still maintain their ancestral customs and traditions, and are virtually untouched by alien influences. Most of the changes have so far taken place among the coastal people, who are being subjected to ever increasing contacts with the world outside. This process of change is being accelerated by the work of missionaries, who have been working for many decades among the local populations. The people of the north and west are mostly Protestants, while those of the south and of the hinterland around Enarotali are Roman Catholics. Those around Fakfak and the Raja Ampat Islands are mostly Moslem. Animism is still practiced by isolated tribes in various parts of the province.

Although Irian Jaya is famed for its Bird of Paradise, the province's fauna is not particularly rich. Almost all the animals here are of the Australian fauna type. Copper, oil, timber, and sea products like fish and shrimps are among the province's main products.