Hildesheim was only connected via Lehrte in the north and with a branch line to Nordstemmen station on the Hanoverian Southern Railway.

It only needed a direct connection to Brunswick to cope with increasing levels of traffic from the iron ore mines in the northern Harz district.

In 1888 the approximately 35 km long link between Hildesheim to the Hanover–Brunswick line at Gross Gleidingen was put into operation.

It does not lead to the major nearby city of Hanover and, until 1960, the old Brunswick station, which was built as a terminus, inhibited through traffic.

These were replaced by Intercity-Express trains in 1993 and since 1998 they have taken the route east of Brunswick via the Weddel loop and Hanover–Berlin high-speed line.

Four years later, the first German Durchgangszug (D-Zug, express train with a connecting corridor) ran over the line, the D 31/32 between Cologne and Berlin, since it formed part of the shortest route.

These were replaced in 1993 by ICE services; since 1998 these have run east of Brunswick over the Weddel loop and the Hanover–Berlin high-speed railway.

[3] In the spring of 2000, the Federal Ministry of Transport examined plans to upgrade the Brunswick–Hamelin–Löhne axis for double track as a southern bypass of the node of Hanover for freight traffic.

[4] The planning approvals for the three sections of double tracking with a total length of 34 km were issued on 14 November 2001, 12 December 2001 and 24 February 2002.

[10] In mid-December 2008, Deutsche Bahn finally notified that it would be calling tenders for the doubling over a length of 34 kilometres.

[12] However, Deutsche Bahn did not call tenders until mid-July 2009, with the contract to be awarded from November 2009 and work to be completed by the end of December 2012.

The service, which was originally scheduled to run every two hours with additional services during the peak hour, had to be reduced in December 2006 due to the difficult financial situation at the Zweckverband Großraum Braunschweig (Regional Association of Greater Brunswick).

From December 2015, the regional trains between Hildesheim and Brunswick have run every hour, continuing over the Weddel loop to Wolfsburg.