Selangor is a state on the west coast of Peninsular Malaysia.  Perak forms the boundary to the north, Pahang to the east, Negeri Sembilan to the south, and the Strait of Malacca to the west.  The Malaysian federal capital, Kuala Lumpur, lies within Selangor's boundaries, but is governed separately.

More than 44 per cent of the population of Selangor are Malay.  About 37 per cent are Chinese, and 17 per cent are Indian.  Most of the population live around Kuala Lumpur.  Expanding industry has led to the building of satellite towns, such as Petaling Jaya, from which many people commute to work in the federal capital.  The head of state of Selangor is a sultan.  The state legislative assembly has 42 seats.
 

Selangor has long been one of the most economically advanced states in the peninsula.  During the period when the British ruled Malaysia as a colony, tin and rubber exports were the foundation of its wealth.  Since the 1960's, these industries declined in importance.  Many of the tin seams are now exhausted.  In the same period, there was rapid expansion of manufacturing, much of it in the Kelang Valley, between Port Kelang and Kuala Lumpur.  Heavy industry includes a major steel-producing plant, but there is also a strong emphasis on high technology production.  The Malaysian car, the Proton Saga, is manufactured near the state capital of Shah Alam.  There is also a large number of food processing plants.

The state has excellent communications, mainly because the federal capital, Kuala Lumpur, lies within its borders.  The main west coast railway runs from north to south through Selangor.  The state is also at the centre of the peninsula's road network, with major roads running from Kuala Lumpur to the north and south, and to the east coast.  The main international port in the peninsula is at Port Kelang, and Malaysia's principal international airport is at Subang.

The Main Range of mountains forms the state's border with Pahang to the east.  The Main Range is heavily forested.  The Selangor, Langat, Kelang, and Bernam rivers rise in the region and flow westward through the state to the Strait of Malacca (Melaka).  From the Main Range, Selangor stretches westward over limestone and sandstone foothills, which have substantial deposits of tin.  West of the foothills is a low-lying plain that runs without break along the coast.  The plain consists of silt and rock debris deposited by the rivers from the Main Range.  Mangrove forests line the coastal margins of the plain.  Behind the mangrove belt, there is much agricultural land, but large areas of swamp and lowland rainforest remain.

Human settlement in the Kelang River valley dates from neolithic times. During the 1300's, Kelang and the surrounding coastal area formed part of the great Javanese empire of Majapahit.  In the 1400's, it came under the control of Melaka, to the south.  In 1511, Melaka fell to the Portuguese, and the Kelang rulers gained greater independence.  But the huge tin resources of their lands attracted many foreign traders.  The Dutch, having taken Melaka from the Portuguese in 1641, attempted to control the local tin trade by building forts at Kuala Linggi and Kuala Selangor.  At the same time, Bugis traders pushed aside the original Minangkabau settlers.  By the mid-1700's, the Bugis had established the present sultanate, with the capital at Kuala Selangor, and were successfully resisting Dutch power.

The rapid expansion of international demand for tin from the mid-1800's transformed the economy of Selangor.  Thousands of Chinese miners arrived to extract tin.  Wealthy Chinese tin miners and the Malay rulers became involved in fierce conflicts for control of the main deposits.  By the 1860's, the state was sliding towards anarchy and civil war, and the trade in tin decreased dramatically.  In the mid-1870's, the British administration in the Straits Settlements intervened to restore order.  In August 1874, they appointed an official resident (government representative) to Selangor.  The sultan remained head of state, the indigenous (local) peoples remained his subjects, but the British ruled.  In 1896, the British completed a scheme to combine Selangor with Perak, Negeri Sembilan, and Pahang, forming the Federated Malay States (FMS), with the federal capital at Kuala Lumpur.  This measure further weakened the political position of the Malay rulers.

At the same time, the economy of Selangor grew substantially.  Tin production expanded most rapidly in the late 1800's.  In the early 1900's, the new export commodity of rubber began to rival tin in importance.  Huge European-owned rubber plantations in Selangor employed large numbers of Indian labourers, recruited from south India.  The plantations were mainly in the area between the foothills and the coast.  Many immigrants also came from the Dutch East Indies (now Indonesia) to cultivate coconuts, fruit, rice, and spices.

At the beginning of the 1900's, Selangor was the most advanced of the Malay states under British administration.  It possessed an excellent network of roads, railways, and ports and a rapidly growing population.

In 1948, Selangor became part of the Federation of Malaya.  On Aug. 31, 1957, the Federation of Malaya became independent from British rule.  Since the 1960's, the economy of Selangor has continued to run in advance of that of the other states in the peninsula.  Selangor now has a substantial manufacturing base and a highly developed modern service sector.  But the state has also seen more acute ethnic tension than anywhere else in the peninsula.  During the Chinese-Malay riots of May 1969, the violence was worst in Selangor.