Riau, propinsi (or provinsi; province), east-central Sumatra, Indonesia. It is bounded by the province of North Sumatra (Sumatera Utara) to the north and northwest, by the Strait of Malacca to the east and Berhala Strait to the southeast, and by the provinces of Jambi to the south and West Sumatra (Sumatera Barat) to the west. Riau includes the islands of Rupat, Bengkalis, Rangsang, and Rantau in the Strait of Malacca. The capital is Pekanbaru, in the west-central part of the province. Area 33,600 square miles (87,024 square km). Pop. (2009 est.) 5,538,367.
Geography
The Batak Plateau and the Padang Highlands of the Barisan Mountains, situated along the western boundary of Riau, are the only major uplands in the province. The Tigapuluh
Mountains, with an average elevation of 2,369 feet (722 metres), thrust
northward near the province’s south-central boundary. A belt of swamps,
fed by the Rokan, Tapung, Siak, Kampar, and Indragiri rivers flowing
eastward from the highlands, extends inward from the coast to a maximum
width of about 150 miles (240 km); swamps also cover the greater part of
Rupat and Bengkalis
islands. The region is subject to occasional flooding, and the coast is
deeply indented by estuaries. The swamp vegetation includes sedge,
pandanus, rattan, and ferns; dense bamboo thickets border the swamps at
many places, and the estuaries are dotted with mangroves.
Riau’s population consists primarily of Malay peoples, and Islam is the predominant religion. The Minangkabau, Batak, and Chinese communities are among the most prominent minority groups.
Agriculture is a major occupation in Riau, with rice, corn (maize), cassava, soybeans, copra
(dried coconut meat), gambier (a plant producing a resin used for
tanning and dyeing), and pepper among the main products. There also are
moderate logging and fishing industries. The principal large-scale
industry is the extraction of petroleum from fields near Pekanbaru.
Sungai Pakning and Dumai, both on the northern coast, have oil
refineries. Other manufacturing activities include food processing,
papermaking, and wood carving. Much of the internal transport is by
riverboat; good roads are confined largely to the hinterland around
Pekanbaru. There is an international airport in Pekanbaru, and several
smaller facilities handle domestic flights.
The region formed part of the Buddhist Srivijaya empire, with its capital at Palembang (in southeastern Sumatra), and served as a base for the conquest of kingdoms on the Malay Peninsula in the 7th century ce. The Hindu Majapahit empire of eastern Java
established supremacy over the region in the 14th century, after the
fall of the Srivijaya empire. Muslim states were established in the 16th
century, following the disintegration of the Majapahit empire. When the
Portuguese seized the Malay state of Malacca in 1511, its last sultan retained Johore (Johor) on the Malay Peninsula and the Riau archipelago at its southern tip. The Dutch
arrived in 1596, and the British followed shortly afterward. Rivalries
between the European powers and attacks by sea pirates adversely
affected the fortunes of the region, which had come under Dutch control
by the end of the 18th century.
After an interval of Japanese occupation (1942–45) during World War II,
the province was incorporated into the newly formed Republic of
Indonesia in 1950 as part of the province of Central Sumatra. In 1957
Central Sumatra was divided into the provinces of West Sumatra, Jambi,
and Riau. At that time, Riau included the neighbouring Riau and Lingga
archipelagos as well as the Anambas, Tambelan, and Natuna island groups
in the waters between the Malay Peninsula and northwestern Borneo. Those island territories were separated administratively from mainland Riau in 2002 to become Riau Islands province.