(pŭn´´jäb') [Pers.,=five rivers], historic region in the NW of the Indian subcontinent. Since 1947 it has been separated into an Indian state and a Pakistani province bearing the same name. The Indus River bounds the region in part of the west and the Yamuna River in part of the east. The five rivers that give Punjab its name, the Jhelum, the Chenab, the Ravi, the Sutlej, and the Beas, merge to form the Panjnad, which flows into the Indus. Except in the north, where there are forested mountains yielding salt and coal, the Punjab is a level alluvial plain. Rainfall is scant and irregular, but extensive irrigation systems using the waters of the great rivers have made possible enormous agricultural productivity. Wheat (by far the leading crop), millet, barley, cotton, and sugarcane are grown, and there are extensive fruit orchards. The Punjab has a large textile industry and much flour milling. Communications (by road, by rail, and on the rivers) are excellent. More than 60% of the population of Punjab is Sikh (see Sikhism).
The region, situated athwart the main approaches to the Indian subcontinent, formed one of the centers of the prehistoric Indus valley civilization, and after c.1500 B.C. it was the site of the earliest Aryan settlements. The Punjab was occupied by Alexander the Great and then by the Maurya empire. Muslims occupied W Punjab by the 8th cent. and firmly implanted Islam. Not until the late 12th cent. did they conquer E Punjab, which even afterward remained predominantly Hindu. Under the Mughal empire the Punjab reached its cultural height. When the empire declined in the late 18th cent., the Sikhs rose to dominance. By the early 19th cent. their territorial aggrandizement brought conflict with the British, who emerged victorious in the two Sikh Wars (1846, 1849) and in 1849 annexed most of the Punjab and made it a province, though some of the princely states were retained.
With the creation of Pakistan in 1947, the Punjab was partitioned approximately along the line between the main concentrations of the Muslim and the Hindu populations. The western portion became the Pakistan province of West Punjab (renamed simply Punjab in 1949; 1998 pop. 72,585,430; c.58,000 sq mi/150,220 sq km) with its capital at Lahore.
The Indian section (c.91,000 sq mi/235,690 sq km) of the Punjab was divided after partition into three areas. The numerous Punjab hill states were merged into the union territory of Himachal Pradesh (now a state), other princely states were formed into the union territory of Patiala and East Punjab States Union, and the remaining area became the Indian state of East Punjab. In 1956 East Punjab and Patiala and East Punjab States Union were merged to form the state of Punjab. In a further reorganization in 1966, Punjab was divided into two states: Hindi-speaking Haryana and Punjabi-speaking Punjab (2001 provisional pop. 24,289,296), 19,764 sq mi (51,189 sq km). The capital of Punjab is Chandigarh. Other important cities in Punjab are Amritsar, Jalandhar, and Ludhiana. A third portion of the former Punjab was added to Himachal Pradesh.
Sikh separatists have sought an independent Sikh state since 1947. The movement grew more militant in the face of attempts by India's central government to suppress the movement through military action, jailings, concessions to moderates, and internal subversion, and during the 1980s thousands died and Prime Minister Indira Gandhi was assassinated. Peace has now returned, but Punjab has not regained its former economic primacy. Punjab is governed by a chief minister and cabinet responsible to a bicameral legislature with one elected house and by a governor appointed by the president of India.