Henry IV of France

25 July 1593, in the royal abbey church

With Paris still closed to him, Henry IV publicly and solemnly abjured Protestantism on 25 July 1593 at the royal abbey church of Saint-Denis, and professed Catholicism.

Renaud de Beaune, archbishop of Bourges, received the king's oath. Monks attended with the cross and the Gospels, and Henry's Catholic profession of faith was written down and signed during the ceremony.

The argument he was answering

The Catholic League's Estates General, convened at Paris in January 1593, had pressed the principle that France must have a Catholic sovereign. Henry concluded that remaining Protestant blocked recognition of his kingship, and announced his intended conversion in May — not, as often repeated, in January.

The League he was answering was led by Charles, duke of Mayenne; his brother Henry, duke of Guise, had been assassinated in 1588.

What the ceremony did not accomplish

The conversion undercut the League's central objection, that France could not accept a Protestant king. It did not deliver Paris or end League resistance.

Paris remained closed to Henry until March 1594, fighting continued, and papal recognition followed only in 1595.

As for the line the day is remembered by — that Paris is well worth a Mass — the attribution is apocryphal, not a documented remark of Henry's.