WEMMERS, JAKOBUS. – Carmelite, missionary, and bishop, born in Antwerp on 21 October 1598, died in Naples on 21 August 1645. In 1617 he professed among the Carmelites of the ancient observance.
After graduating in theology, he went to Rome, where he established relations with the priests of the Abyssinian hospice of S. Stefano, systematically studying the language of Ethiopia. In 1638, his great work Lexicon Actiopicum (4to, 319 pp.) was published by the Propaganda press, followed by a grammar of the same language with an index of Latin words referring to the dictionary (100 pp.), the first scientific study of the Ethiopian language, still considered a masterpiece. In recognition of the reputation he had acquired through these studies, in 1640 he was appointed by the Congregation of Propaganda Fide prefect of the mission of Ethiopia, where he worked with great success, thanks not only to his apostolic zeal but also to his linguistic expertise. Having returned to Rome, in 1645 he was elected bishop of Memphis (Cairo) and apostolic vicar for the mission of Ethiopia.
Consecrated on 5 June 1645 in Rome, he set out for his field of work, but in Naples, while awaiting embarkation, he was struck by death.