The codex was made in Fustat (Old Cairo) at the start of the 11th century. Its colophons record the scribe Samuel ben Jacob and state that the text was prepared and corrected from manuscripts pointed by Aaron ben Asher, tying it to the most authoritative branch of the Tiberian tradition. Beyond its text it is a fine object in its own right, with sixteen illuminated "carpet pages" of geometric ornament and micrography (patterns formed from minute writing).
Its modern history runs through the collection of Abraham Firkovich, a 19th-century Karaite scholar who gathered manuscripts across the Near East. His collection was acquired by the Imperial Public Library in St Petersburg, and the codex has remained there, through the city's renaming to Leningrad and back, as MS Firkovich B 19A, now in the National Library of Russia.
In the 20th century the manuscript acquired a new prominence. When Paul Kahle sought a complete, early Masoretic text as the base for the third edition of Rudolf Kittel's Biblia Hebraica, he chose the Leningrad Codex. It has served that role ever since, in Biblia Hebraica Stuttgartensia and the in-progress Biblia Hebraica Quinta, and it was among the first major Hebrew manuscripts to be fully photographed and digitised, making the oldest complete Hebrew Bible freely consultable.