The states of Saxe-Weimar-Eisenach, Saxe-Coburg and Gotha, Prussia and the Electorate of Hesse negotiated from 1840 on the building of an east-west railway.

The name Frederick William Northern Railway is not only applied to the line between Kassel and Bebra, but also to the whole route between Warburg and Gerstungen.

Thus, from the Hessian perspective, the Frederick William Northern Railway was the first stage of a plan to build a rail network in the Electorate.

The eastern branch from Bebra to Fulda and Hanau (the Frankfurt–Bebra line),—all Hessian cities and thus of highest priority for the Electorate—crossed difficult topography and therefore was not completed until Hesse-Kassel was annexed by Prussia in 1866.

On 1 July 1845 the groundbreaking ceremony was celebrated for the construction of the line and by 29 December 1849 the entire route was opened to traffic.