DESMAESTRE, JONAH (late 14th century), Majorcan scholar. Desmaestre was the head of the local yeshivah. Despite his piety and full devotion to Torah and talmudic studies, he was well versed in philosophy and mysticism, mathematics and astronomy. Majorca was an important center of astronomical studies. He was the father-in-law of Simeon b. Ẓemaḥ *Duran, and his name is mentioned several times in the responsa of his descendants. In the documents of the kingdom of Aragon, he is called Biona del Maestre. Desmaestre studied in the yeshivah of Barcelona under Perez ha-Kohen. Considered one of the most pious men of his generation, Desmaestre received permission to travel to Aragon to make representations to the king on behalf of his community. With Ḥasdai *Crescas he did much to promote the interests of the Jews of the Kingdom of Aragon. He acted as the leader of the Jews of Majorca and joined forces with the leaders of the other communities in the Kingdom to improve the conditions of the Jews. In 1383, he succeeded in obtaining a grant of privilege from Pedro iv of Aragon, which reinforced the authority of the communal leadership and protected it from harassment by converts to Christianity. He vigorously defended the Jews of Lérida who had been accused of buying the consecrated Host. There is no evidence to confirm the report that Desmaestre died as a martyr in the persecution of 1391.
Baer, Urkunden, 1 (1929), 542f., index s.v.Biona del Maestre; Baer, Spain, index s.v.Jonah Desmaestre; H. Jaulus, in: mgwj, 23 (1874), 250.