CESARIO di SAN BONAVENTURA. – Carmelite missionary, in the world Giovanni, son of the distinguished Orientalist Pietro Bertius. Born on 16 March 1615 at Leiden (Holland) to Protestant parents; died on 27 October 1662. Having become a Catholic, he joined the Order of the Discalced Carmelites in Paris on 18 July 1632 and initiated the Carmelite missions in Holland, where he founded a station at The Hague (1648). After bringing many heretics and apostates to the Catholic faith, he was recalled (1657) to Paris. He was then appointed prior of the convent in Malta, where he died.
In addition to various reports on the mission in Holland, still in manuscript, he published: 1) Tractatus de S.mo Eucharistiae Sacramento, against the Protestants; 2) Breve compendium doctrinae christianae (Brussels 1650).