The aim of this MRSEI is to finance the exploration of a network whose work will be directed towards the preparation of a SE intended to pave the way for a new phase in the study of the forms of European "feudalism". This project, led by historians, will be interdisciplinary and multisectoral: it will involve lawyers, linguists, computer scientists, geomatics specialists, archivists and museum conservators. The SE mobility project that we are carrying out will consist of building a common frame of reference, based on historiographic heritages, in order to reopen the question of the modalities of domination over land and people, in a comparative perspective, in order to get the questions out of the national ruts that still structure them. It will thus be possible to produce a renewed, global and long-term history of the socio-political structures that organized Europe from the central Middle Ages to the 18th century and constituted the model for its expansion into the Americas, which were largely colonized and exploited using "feudal" tools. The first task of the MRSEI will be to federate dispersed researchers around this object and to delimit the consortium in view of the SE. It will require meetings with the different partners already contacted or that we intend to contact in order to compare our methodologies, our research perspectives, and to evaluate the possibilities of working together as well as the existing support from the institutions to which we belong. Once the consortium is formalized, discussions will aim at making a critical assessment of the legacy of works published until the 1990s to bring this historiography into dialogue with more contemporary issues. These discussions will prepare a break with the historiography and provide the state of the art necessary for the SE. Further meetings as well as video-conferences will allow to define the common objectives of the SE and to determine the form and content of the resulting deliverables. The consortium will be composed of five to seven academic institutions, whose researchers will benefit from the SE mobilities. One or two non-academic partners will be added, to be specified during the MRSEI: archival foundations dedicated to the nobility or museums with which a strategy of valorization of heritage and archives related to feudal and seigniorial issues will be set up. On the scientific level, the objective of the SE is to produce tools that will be accessible online, multilingual, and that will make it possible to open up historiographies on feudalism and the seigniorial system, to better understand its history over the long term and its expansion, and to better grasp the differences and common points between these modes of domination over the land and men in space and time. On the pedagogical level, the SE will work on a strategy of valorization that will fluidify the relationship between higher and secondary education and that will place the digital tools developed for the project at the heart of learning, by targeting both students and teachers. In terms of cultural heritage, the idea will be to work with museums and/or private foundations to build tools for the diffusion of research (traveling exhibitions for museums, beautiful popularization books, signage or guides for new ways of visiting certain places, tools for the promotion of heritage based on our objects) in accordance with the objectives of safeguarding and promoting European heritage, which is immensely rich in this area. Developing this network within the CRH (UMR CNRS/EHESS) is a crucial asset: the EHESS has considerable experience thanks to the multiple European Union and ANR funding it has already obtained, and because it has already implemented RISE, the predecessor of SE.