Regrouping was first conceived in 1904 and by 1944 all company-managed railways were taken over by the state. After World War II, railways were divided into three territorial divisions, namely Western, Eastern and Southern. Eastern division consisted of East Indian Railway, Oudh & Rohilkund Railway, Bengal & North Western Railway, Rohilkund & Kumaon Railway, Assam Bengal Railway, Bengal Nagpur railway and East Bengal Railway.
The Bengal Nagpur Railway portion was separated in 1955 to form the South Eastern Railway. Sealdah Division was added to EIR in 1947. In 1952, the upper Divisions became part of Northern Railway, leaving the three lower Divisions and Sealdah Division in Eastern Railway. Dhanbad Division was formed in 1964, Mughulsarai Division in 1975 and Malda Division in 1984 as part of ER.
A new line from Garhwa Road to Chopan and Chunar, with a branch to Singrauli was constructed by Northern Railway and handed over to ER. These sections became part of Dhanbad Division.
In the early 1990s, following large scale conversion of metre gauge lines into broad gauge, considerable redrawing of traffic patterns took place. An expert committee suggested that 4 new zones should be created namely, North Western with headquarters at Jaipur, North Central with headquarters at Jabalpur, East Central with headquarters at Allahabad and South Western with headquarters at Bangalore.
In 1996, jurisdictions of the proposed zones were changed in some cases and the headquarters of East Central railway was changed from Allahabad to Hajipur. It was also planned to form an East Coast zone with headquarters at Bhubaneswar.
Moreover, on public demand, a new zone, South Eastern Central Railway was formed with headquarters at Bilaspur, and the headquarters of South Western Railway was shifted from Bangalore to Hubli.
East Central zone, with headquarters at Hajipur started functioning from the 1st of October, 2002. This was to consist of Samastipur and Sonepur divisions of North Eastern along with Danapur, Mughalsarai and Dhanbad divisions of Eastern. The North Western zone with its headquarters at Jaipur also started functioning from the same date. Five other zones viz, East Coast Railway, North Central Railway, West Central Railway, South East Central and South Western Railway have started functioning from 1 April, 2003.
Eastern Railway of today consists of Sealdah, Howrah, Asansol and Malda Divisions.
ON THE THUMBNAILS TO ENLARGE PICTURES)