An unpopular insistence on the formalities was attributed to him, at a time of tension between the Jesuits and the French Catholic Church.
[8] The pamphlet war drew in Isaac Casaubon, and Eudaemon-Joannis was attacked by name by John Prideaux.
[9] Eudaemon-Joannis was sometimes considered to be a pseudonym in this debate, for example for Scioppius;[10] or for the French Jesuit Jean L'Heureux, something repeated in the Criminal Trials of David Jardine in the 19th century.
[11][12][13] A 1625 work, the Admonitio attacking Louis XIII, that appeared under the pseudonym G.G.R., has been attributed both to Eudaemon-Joannis and to Jacob Keller.
[14] Cardinal Richelieu believed Eudaemon-Joannis to be the author; Carolus Scribani was another suspect, and François Garasse was questioned, as part of the struggle of Gallicanism against the Jesuits.