Johannes Baptista van Neercassel (Gorinchem, 1626 – Zwolle, 6 June 1686) served as apostolic vicar of the Dutch Mission, heir of the Roman Catholic Archdiocese of Utrecht, from 1661 to 1686.

In June 1662 he was appointed coadjutor to De la Torre's successor Boudewijn Catz and was consecrated titular bishop of Castorie.

Neercassel was an admirer of Charles Borromeo and shared the Archbishop of Milan's views of the necessity of improving the quality of the clergy, both educationally and morally.

Rogier said "...that the existence of Catholic enclaves in the nineteenth-century Netherlands was the result of the protection and patronage of missionary priests during the Dutch Republic by noble families who had, both secretly and openly, opposed the proselytising policies of the Calvinist authorities.

Although there was little thought of reprisals by the Protestants, Van Neercassel judged it expedient to leave the Dutch Republic temporarily, continuing the Mission's work first from Antwerp and later from Huissen, where he founded a Latin school in 1676.

[1] A respected figure on the international stage, with an excellent network of contacts in France and Rome, Johannes van Neercassel represented spiritualist Jansenism and had good relations with Port-Royal.

In time the Jesuits succeeded in undermining his position and his theological work Amor poenitens (1683) was put on the Index of Prohibited Books after his death.