Khagaria, as a district, is only twenty Years old. Earlier, it was a part of the district of Munger, as a subdivision. The sub-division of Khagaria was created in the Year 1943-44. It was upgraded as district, with effect from 10th May, 1981, vide Government of Bihar notification no. 7/T-1-207/79 dated 30th April,1981. As a sub-division of the old district of Munger, Khagaria was the youngest, in terms of creation of sundivision, before independence. The other three older subdivision were Munger sadar, Begusarai and Jamui. The Jamui sub-division was created on 22nd July,1864 and Begusarai sub-division on the 14th February 1870.
Khagaria was created as a separate sub-division mainly because of the difficulties arising out of a lack of easy means of communications. Railways were a very old means of communication in this district. As per the Gazetteer of 1960,this Sub-division had three railway lines - the north Eastern Railway, passing west to East had four Stations – Khagaria, Mansi, Maheshkhunt and Pasraha . One branch Line shot off from Khagaria passing through Olapur and Imli, while another branch line shot off from Mansi, which went up to Saharsa. This Mansi- Saharsa branch line, during that period was however disturbed during rains between Katyani Asthan and Koparia, a distance of 6 miles, which had to be covered by boats. Apart from railways, the other means of communication was roads, which were in a very bad shape. The only metalled road at that time was 22 mile long Maheshkhunt- Aguawani ghat road, which was still under construction. During that period Khagaria- Parihara- bakhri Road was also under construction and National Highway linking Moakamaghat to Assam was under contemplation.