[1] Its headquarters is located in Jaleshwar, a neighbouring town of the historical city of Janakpur.

Jaleshwar lies at a few kilometres distance from the Nepal-India border and has a majority Maithili population.

At the time of the 2011 Nepal census, Mahottari District had a population of 627,580.

15.2% were Yadav, 13.4% Musalman, 6.5% Dhanuk, 5.8% Koiri/Kushwaha, 5.1% Terai Brahmin, 4.1% Teli, 3.7% Musahar, 3.6% Chamar/Harijan/Ram, 2.5% Khatwe, 2.4% Dusadh/Paswan/Pasi, 2.4% Sudhi, 2.3% Magar, 2.2% Nuniya, 1.8% Hill Brahmin, 1.6% Baraee, 1.6% Chhetri, 1.6% Tatma/Tatwa, 1.6% Tharu, 1.5% Bin, 1.5% Kalwar, 1.5% Tamang, 1.4% Mallaha, 1.3% Hajam/Thakur, 1.3% Sonar, 1.1% Kanu, 1.1% Kewat, 1.0% Dhobi, 0.9% Kurmi, 0.9% Lohar, 0.8% Halwai, 0.7% Kami, 0.7% Newar, 0.7% Rajput, 0.6% Dhunia, 0.6% Kumhar, 0.5% Kathabaniyan, 0.4% Bantar/Sardar, 0.4% Danuwar, 0.4% Kayastha, 0.4% other Terai, 0.3% Damai/Dholi, 0.3% Mali, 0.2% Badhaee, 0.2% Dom, 0.2% Gaderi/Bhedihar, 0.2% Gharti/Bhujel, 0.2% Kumal, 0.2% Sanyasi/Dasnami, 0.1% Amat, 0.1% Majhi, 0.1% Punjabi/Sikh, 0.1% Rai, 0.1% Sarki, 0.1% Sunuwar, 0.1% Thakuri and 0.2% others.

These are as follows:[8] The 2011 National Population and Housing Census by the government of Nepal identifies 77 municipalities and village development committees (VDC) within the Mahottari District.