Alvarium is an identitarian organisation based in Angers, founded in 2017 by Jean-Eudes Gannat. It is dissolved on November 17th 2021 by the French governement for inciting to discrimination and hate on the basis of race, sexuality, gender and religion and xenophobic amalgam between immigration, Islam and terrorism. (They have however appealed the decision, which has a suspensive effect until a new/final decision is made, which means they can still operate until then).
The group, similar to other identitarian organisations such as Bastion Social or Génération Identitaire, advertised social activities and help to white French people in need, claiming a social-catholic inspiration.

https://serviam-alvarium.fr/
https://www.legifrance.gouv.fr/jorf/id/JORFTEXT000044336429
https://lahorde.samizdat.net/angers-une-soupe-impopulaire-et-rance
https://raaf.noblogs.org/