Produced during the second half of the 13th century, the Manuscrit du Roi (Paris BnF fr. 844) contains 602 musical compositions from multiple musical and linguistic traditions. The codex contains songs of the trouvères and troubadours, motets, instrumental works, and some religious pieces. Certain gaps were filled in a few years after the first phase of publication: some additional pieces were added, also from multiple provenances. By assembling several different repertoires and using multiple languages ??(Old French, Old Occitan, Old Gallicized Occitan, and Latin), the codex is an ideal resource for the study of secular sung traditions in the thirteenth century. The interdisciplinary project Manuscrit du Roi’. Image, Texte Et Musique focuses on understanding the crafting and history of this codex, both in its material conception and in the processes of composition of the works, as well as its modern reception within the contemporary musical interpretation of medieval music. The project also focuses on the relationship between secular and religious registers to delineate mutual influences in musico-textual composition. MARITEM will develop an Open Access web interface that will contain a musico-textual digital edition encoded in XML-TEI / MEI, a search engine that will provide the ability to cross-reference textual and musical data, an interactive study of the manuscript, and a collection of scores intended for interpretative use. The interface will eventually serve as a prototype for the publishing and indexing of other music in French, Occitan and German. The originality of the project lies in the study of this composite manuscript in all of its many facets, a study only made possible by new digital technologies. Medieval musicologists will be able to work together with philologists in order to offer new answers about the history of textual traditions, present an innovative perspective, and develop new hypotheses on the written transmission of texts and corpora. Musicologists and linguists will also find convincing answers to problems thanks to the possibilities for vocal experimentation, which have never been attempted for these corpora, in particular around delimiting rhythmic sequences in unmeasured monodies. The project will also renew the relationship between musical curve and the sound of languages. Thanks to MARITEM, the profane practices of the end of the 13th century will be better known, as much in their composition process as in the modalities of their performance. The different repertoires of the codex will here be treated as a whole, as represented in the written record.