Assam ([æˈsæm], ; Ôxôm) is a state of India in the north-eastern region. Its capital is Dispur, located within the municipal area of Guwahati city. Located south of the eastern Himalayas, Assam comprises the Brahmaputra and the Barak river valleys along with the Karbi Anglong and the North Cachar Hills with an area of 30,285 square miles (78,438 km²). Assam is surrounded by six of the other Seven Sister States: Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura and Meghalaya. Geographically Assam and these states are connected to the rest of India via a narrow strip of land in West Bengal called the Siliguri Corridor or "Chicken's Neck".
Assam shares international borders with Bhutan and Bangladesh; and cultures, peoples and climate with South-East Asia – important elements in India’s Look East policy. Assam became a part of the British India after the British occupied the region following the First Anglo-Burmese War of 1824–1826.
Assam is rich in culture, ethnic groups, languages/dialacts spoken and literature. It is known for Assam tea, large and old petroleum resources (the first oil reserves of India were discovered in Assam in the late 19th century), Assam silk and for its rich biodiversity. Assam has successfully conserved the one-horned Indian rhinoceros from near extinction, along with the tiger and numerous species of birds, and it provides one of the last wild habitats for the Asian elephant. It is becoming an increasingly popular destination for wildlife tourism, and Kaziranga and Manas are both World Heritage Sites. Assam was also known for its Sal tree forests and forest products, much depleted now. A land of high rainfall, Assam is endowed with lush greenery and the mighty river Brahmaputra, whose tributaries and oxbow lakes provide the region with a unique hydro-geomorphic and aesthetic environment.
Assam state and adjoining regions have evidences of human settlements from all the periods of the Stone ages, but there are no archeological evidence of bronze- or iron-age culture. The hills at the height of 1,500–2,000 feet (460 to 615 m) were popular habitats probably due to availability of exposed doleritic basalt useful for tool-making.
According to a late text, Kalika Purana (c.7th–8th AD), the earliest ruler of Assam was Mahiranga Danav of the Danava dynasty, which was removed by Naraka who established his the Naraka dynasty. The last of these rulers, also Naraka, was slain by Krishna. Naraka's son Bhagadatta became the king, who, it is mentioned in the Mahabharata, fought for the Kauravas in the battle of Kurukshetra with an army of kiratas, chinas and dwellers of the eastern coast.
Samudragupta's 4th century Allahabad inscription mentions Kamarupa (Western Assam) and Davaka as frontier kingdoms of the Gupta Empire. Davaka was soon absorbed by Kamarupa kingdom, which grew into large kingdom that spanned from Karatoya river to Sadiya and covered the entire Brahmaputra valley and, at times, North Bengal and Northern Bangladesh.
Ruled by three dynasties Varmanas (c.350–650 CE), Mlechchha dynasty (c.655–900 CE) and Kamarupa-Palas (c.900–1100 CE), from their capitals in present-day Guwahati (Pragjyotishpura), Tezpur (Haruppeswara) and Durjaya respectively. Country was 10,000 li in circuit and capital city Pragjyotishpura was about 30 li. Kamrupi kings claims their descent from Narakasura, an immigrant from Aryavarta.
In the reign of the Varman king, Bhaskar Varman (c. 600–650 AD), the Chinese traveler Xuan Zang visited the region and recorded his travels. Later, after weakening and disintegration (after the Kamarupa-Palas), the Kamarupa tradition was somewhat extended till c. 1255 AD by the Lunar I (c. 1120–1185 AD) and Lunar II (c. 1155–1255 AD) dynasties.
Two later dynasties, the Ahoms and the Koch. The Ahoms, a Tai group, ruled Upper Assam for nearly 600 years (1228–1826 AD) and the Koch, a Tibeto-Burmese, established sovereignty in c. 1510 AD. The Koch kingdom in western Assam and present North Bengal was at its zenith in the early reign of Naranarayana (c. 1540–1587 AD). It split into two in c. 1581 AD, the western part as a Moghul vassal and the eastern as an Ahom satellite state. Since c. 13th AD, the nerve centre of Ahom polity was upper Assam; the kingdom was gradually extended till Karatoya River in the c. 17th–18th AD. It was at its zenith during the reign of Sukhrungpha or Sworgodeu Rudra Simha (c. 1696–1714 AD). Among other dynasties, the Sutiya Kingdom ruled north-eastern Assam and parts of present Arunachal Pradesh and the Kacharis ruled from Dikhow River to central and southern Assam. With expansion of Ahom kingdom, by c. 1520 AD the Sutiyas areas were annexed and since c. 1536 AD Kacharis remained only in Cachar and North Cachar more as an Ahom ally then a competing force. Despite numerous invasions, mostly by the Muslim rulers, no western power ruled Assam until the arrival of the British. Though the Mughals made seventeen attempts to invade they were not successful. The most successful invader Mir Jumla, a governor of Aurangzeb, briefly occupied Garhgaon (c. 1662–63 AD), the then capital, but found it difficult to control people making guerrilla attacks on his forces, forcing them to leave. The decisive victory of the Assamese led by the great general Lachit Borphukan on the Mughals, then under command of Raja Ram Singha at Saraighat (1671) had almost ended Mughal ambitions in this region. Mughals were finally expelled from Lower Assam during the reign of Gadadhar Singha in 1682 AD.
In the later part of 18th century, religious tensions and atrocities of nobles led to the Moamoria rebellion, resulting in tremendous casualties of lives and property. The rebellion was suppressed but the kingdom was severely weakened by the civil war. Political rivalry between Prime Minister Purnananda Burhagohain and Badan Chandra Borphukan, the Ahom Viceroy of Western Assam, led to the invitation of Burmese by the latter, in turn leading to three successive Burmese invasions of Assam. The reigning monarch Chandrakanta Singha tried to check the Burmese invaders but he was defeated after fierce resistance. A reign of terror was unleashed by the Burmese on the Assamese people, who fled to neighbouring kingdoms and British-ruled Bengal. The Burmese reached the East India Company's borders, and the First Anglo-Burmese War ensued in 1824. The war ended under the Treaty of Yandabo in 1826, with the Company taking control of Western Assam and installing Purandar Singha as king of Upper Assam in 1833. The arrangement lasted till 1838 and thereafter the British gradually annexed the entire region. Initially Assam was made a part of the Bengal Presidency, then in 1906 it was a part of Eastern Bengal and Assam province, and in 1912 it was reconstituted into a chief commissioners' province. In 1913, a legislative council and, in 1937, the Assam Legislative Assembly, were formed in Shillong, the erstwhile capital of the region. The British tea planters imported labour from central India adding to the demographic canvas. After a few initial unsuccessful attempts to free Assam during the 1850s, the Assamese joined and actively supported the Indian National Congress against the British from the early 20th century, with Gopinath Bordoloi emerging as the preeminent nationalist leader in the Assam Congress. Bordoloi's major political rival in this time was Sir Saidullah, who was representing the Muslim League, and had the backing of the influential Muslim cleric Maulana Bhasani.
In 1947, Assam including the present Arunachal Pradesh, Nagaland, Mizoram and Meghalaya became a state of the Union of India (princely states, Manipur and Tripura became Group C provinces) and a district of Assam, Sylhet, chose to join Pakistan.
Since 1947, with increasing economic problems in the region, separatist groups began forming along ethnic lines, and demands for autonomy and sovereignty grew, resulting into fragmentation of Assam.
Since the mid-20th century, people from present Bangladesh have been migrating to Assam. In 1961, the Government of Assam passed a legislation making use of Assamese language compulsory. It had to be withdrawn later under pressure from Bengali speaking people in Cachar. In the 1980s the Brahmaputra valley saw a six-year Assam Agitation triggered by the discovery of a sudden rise in registered voters on electoral rolls. It tried to force the government to identify and deport foreigners illegally migrating from neighboring Bangladesh and changing the demographics. The agitation ended after an accord between its leaders and the Union Government, which remained unimplemented, causing simmering discontent.
The post 1970s experienced the growth of armed separatist groups like United Liberation Front of Asom (ULFA) and National Democratic Front of Bodoland (NDFB). In November 1990, the Government of India deployed the Indian army, after which low-intensity military conflicts and political homicides have been continuing for more than a decade. In recent times, ethnicity based militant groups have also mushroomed. Regional autonomy has been ensured for Bodo-Kachari community in Bodoland Territorial Council Areas (BTC), for the Karbis in Karbi Anglong and for the people of Dima Hasao district after agitation of the communities due to sluggish rate of development and general apathy of successive state governments towards indigenous communities.