Munger district is a district of Bihar state with its administrative headquarters located at Mungar town. Regarding the etymology of Munger, there are several theories. The natives of the district believe that the district got its present name from its ancient name Mudgagiri. Its ancient name is mentioned in the great epic Mahbharata and the Munger copper plate inscription of Devapala. Whereas according to some other legends, the district is named after the renowned sages i.e. either Mudgala or Maudgalyayana. Most of the part of Angamaha janapada came under the territory of today’s Munger district. During the Mahabharata era it believes that this region was a part of Karna’s kingdom. At the time of Pala rule, they made Mudgagiri i.e. the present Munger district was their capital. Then the East India Company came to India and captured its entire eastern part. But before that one last big battle was fought by Bengal Nawab Mir Kasim, who built there a well known fort with three gates and the Ganges on its fourth sides. Throughout the British rule Munger was popularly called as Monghyr. At present it is a part of the Red Corridor.

Geographically, the district lies at 25°38'N latitude, 86°46'E longitude and 65 m Altitude. In the year 2021, there was a total 20.16% forest area of total geographical area. The district encompasses a geographical area of 1,419 sq kms. and it is bounded by Khagaria district on the north east, Begusarai district on the north west, Banka district on the south east, Jamui district on the south west, Bhagalpur district on the east and Lakhisarai district on the west. The climate of the district during the summer remains extremely hot. Most of its rainfall occurs during the monsoon season. The actual rainfall in the district was 1274.9 mm in the year of 2021-22.

Administration wise, the district has 3 sub-divisions namely Munger Sadar, Kharagpur and Tarapur. Further, these sub divisions are divided into 9 blocks including Sadar, Jamalpur, Bariarpur, Dharhara, Kharagpur, Tetia Bambar, Tarapur, Asarganj and Sangrampur. There are 1 Lok Sabha seat and 3 Assembly constituencies in the district. Moreover the district comprises 7 towns and 858 villages. The administrative language in the district is Hindi.

According to 2011 census the district has a population of 13,67,765 out of which 7,29,041 are males and 6,38,724 are females. The district has a sex ratio of 876 females for every 1000 males. During the year 2001-2011 the population growth rate in the district was 20.21% including 19.96% were males and 20.50% were females. As per 2011 census the major religion in the district is Hindu with 91.56% of the total population. The population density in the district is 964 persons per sq. km. According to 2011 census the principal language in the district is Hindi with 92.57%. In the year 2020 the number of live births in the district was 30,930 out of which 15,719 were males and 15,210 were females. In the same year the number of deaths in the district was 5,590 out of which 3,421 were males and 2,169 were females.

The economy of the district is solely based on agriculture. Some of its chief agriculture products are paddy, wheat, lentils, etc. Every year a huge chunk of revenue comes from these agricultural products. Industrially also this district is quite develop. Jamalpur, a place in the district has a workshop of the Indian Railway which is the Asia's largest and oldest railway workshop. The tobacco and gun manufacturing factories are very common in the district which as well helps in its economy to some extent. Some small scale industries are also found in and around the city. In 2006, the Ministry of Panchayati Raj declared Munger as one of the country's 250 most backward districts and currently receiving funds from the Backward Regions Grant Fund Programme (BRGF). In the year 2011-12 the gross domestic product in the district was Rs. 4,54,128 lakh at current price and Rs. 2,79,268 lakh at constant prices in the year 2004-2005. In the year 2011-12 the net domestic product in the district was Rs. 3,95,990 lakh at current price and Rs. 2,38,853 lakh at constant prices in the year 2004-2005.

There are numerous educational institutions in the district. Some of its reputed educational institutions are Biswanath Singh Institute of Legal Studies, Deo Sundari Memorial College, K.K.M. College, C.N.B. College, Indira Gandhi Mahila College, International College, Sanjay Gandhi Memorial Mahila College, Balmiki Rajniti Mahila Mahavidyalaya, etc. As per 2011 census the literacy rate in the district is 70.46% including 77.74% are males and 62.08% are females. The number of literates in the district is 8,01,817 out of which 4,73,741 are males and 3,28,076 are females.

Brahmanand Mandal, a distinguished Indian politician was born on 14th January, 1947 at Jhawa, Katihar in the Munger district. He served as a member of the Lok Sabha from Munger constituency for three terms under three different political parties i.e. in 1991, as a member of the Communist Party of India, in 1996 as a member of the Samata Party and in 1999 as a member of the Janata Dal (United).

Every year numerous travellers from different part of the world come to this district to enjoy its places of historical importance, religious significance and natural beauty. Chandika Astahan, situated at a distance of just one kms. from Munger town. It is a Siddhpith and considered to be one of the most sacred and sanctified temples. Kastaharni Ghat is a pious bathing place which expels all pains of life. Devotees from far distance place come to this place to take a bath in this ghat. Sita Kund, situated 4 miles away east of Munger town contains hot springs and there is also a Ramkund, a reservoir of cold water to the north. Sri Krishna Vatika, an enchanting garden located opposite to Kashtaharni Ghat has two adventurous "Surangs" (tunnels). Bhimbandh, a village situated in the Kharagpur sub-division has some hot springs, called Tatal-pani (Tapta-pani). Some other illustrious centres of attraction are Rameshwar Kund, Manpathar, Ucheswar Nath, Pirpahar, Kharagpur Lake, Malnipahar, Maruk, Rishikund, etc.