 It was granted urban-type settlement status in the 1950s, after a period of growth following the construction of the western section of the Baikal–Amur Mainline, and renamed Zheleznogorsk ("Iron Mountain Town").With the completion of a major ore processing plant, town status was granted in 1965 under the present name, the suffix "Ilimsky" added to differentiate from other towns of the same name.Within the framework of administrative divisions, Zheleznogorsk-Ilimsky serves as the administrative center of Nizhneilimsky District, to which it is directly subordinated.