Area : 1,729 sq km
Total Population : 11,51,050 (undivided Sivasagar)
Male : 5,89,216
Female : 5,61,834
Sex Ratio : 954 female per 1000 male
Density : 431 persons per sq km
Literacy Rate : 80.41%
Male : 85.84%
Female : 74.71%.
District HQ : Sivasagar
Sub-Division : Two.
Sub-Division : HQ
Boundaries : Brahmaputra river and Dibrugarh District on the north; Charaideo and Dibrugarh on the east; Charaideo district and Nagaland on the south; and Jorhat on the west.
Rivers & Tributaries : Dikhow, Dimow, Jhanji, Disang.
Important Places : Sivasagar, Charaideo, Gargaon, Jhanji, Nazira. 360 km east of Guwahati. Sivasagar, erstwhile Rangpur, is full of historic relics bearing testimony to the 600 years of the Ahom rule. Rangpur literally meaning ‘The City of Joy’ occupied a very significant and unique place during the glorious Ahom rule as its 4th capital. Sivasagar was the capital of Ahom kingdom from 1699 to 1788 in which yearAhom king Gourinath Sinha with about ten thousand followers had to flee this capital at the height of Moamaria rebellion. In the early part of 191″ centuary when the Burmese invasion took place, an army of the British East India Company under Colonel Richardson came to the rescue of Ahom king and vanquished the Burmese invaders. With the Treaty of Yandabo in 1826, the East India Company established the headquarters of administration of Upper Assam region at Joysagar, 5 km to the south-west of present Sivasagar town in the year 1826. In 1913 the headquarter of Sivasagar district was shifted to Jorhat. In 1983 Sivasagar was declared a new district with its headquarter in Sivasagar town. The climate is highly humid with abundant rainfall. The nearest railway junction is Simalugtiri, 16 km away from Sivasagar. Ahom, Koch. Chutiya, Mishing, Deori. Kachari and other ethnic communities inhabit the district. The headquarter of the district, Sivasagar town is constantly haunted by memories of a glorious past of Ahom era. The town, which proudly carries many historical remnants, is 360 km away from Guwahati. The ancient name of Sivasagar was Kolonchuper In 1734, King Shiva Singha’s wife, Her highness queen Bor Raja Ambika got dug a majestic pond in this place and named the pond after the name of her husband. According to some other historians the pond got the name Sivasagar as it was dedicated to Lord Shiva. The area of this pond is 129 acres which is locally known as Borpukhuri The names of the four boundaries of the pond are Cherekapar (east), Dhuliapar (South). Jayorapar (north) and Kathpar (west). The water level of the pond is higher than the ground level of the town. The three temples. — Shivadoul. Vishnudoul and Devidoul on the banks of the pond forms the centre of the town. From the name of this pond, the town got the name Sivasagar. American Baptist Missionaries tried their best to work for the development of Assamese language. literature and culture from this town The first Assamese news magazine Orunodoi was published in 1846 from Sivasagar Sivasagar is the nerve centre of culture and learning of the district. Besides many ancient relics like Rang Ghar. Talatal Ghar etc. there is also a Tai Museum in Sivasagar. It was established in 1991. It is one of the important tourist spot of the State.
Nazira is a sub-division of Sivasagar and the name of the sub-divisional town. Nazira houses the eastern regional headquarters of ONGC. At a stone’s throw from there is Gargaon, the one time principal capital of the Ahom Kings, where major attraction is Kareng Ghar, a seven storeyed palace built by 18’h century architects. Rudrasagar, Gourisagar, Joysagar etc. are some of the important places of Sivasagar district. On 15 August, 2015 Assam Chief Minister Tarun Gogoi announced the formation of a new district named Charaideo.This district is curved out of Sivasagar district. Due to creation of the new district, the area, population etc. of Sivasagar district is affected.