Mar Shemʿon IV Basidi (died 20 February 1497) was the patriarch of the Church of the East in the last quarter of the 15th century.
[3] Shemʿon's Arabic surname, Basidi, indicates that he or his family came from the village of Beth Sayyade in the vicinity of Erbil.
According to him, "the Church was at peace, the convents and brothers enjoyed freedom, the ruined monasteries were restored, the degrees of priests and levites multiplied, and the faithful were blessed by the intercession of" the Aq Qoyunlu ruler Yaqub Beg.
Another manuscript note from 1488, specifically states that Shemʿon IV successfully intervened with Yaqub to have churches reopened in the eastern districts.
Apparently, one of Yaqub's subordinates had begun enforcing the restrictive laws against Christians strictly sometime before 1484, leading the destruction and closure of many churches.