 The Infanta of Spain, Isabella Clara Eugenia is best placed in the contest to the throne of France as many members of the ultra-Catholic League seemed willing to accept her as long she married a French prince.Favoring the conversion of Henry of Navarre to Catholicism, an act that would solve everything, the Duke of Mayenne convened the Parliament to decide the issue when on May 17, Henry of Navarre announced his intention to convert.To get him to move from intention to action, in June 28, Parliament made the "Arrêt Lemaistre" (named after the president of the Parliament of Paris, Jean Le Maistre) that does not make any principle subordinate to another but demands respect for all the fundamental laws of which it highlights consistency, supplementing them with the law of Catholicity.