Portrait of John III from a 15th-century manuscript
wikipediaJohn III Doukas Vatatzes, Latinized as Ducas Vatatzes (Greek: Ιωάννης Γ΄ Δούκας Βατάτζης, Iōannēs III Doukas Vatatzēs, c. 1193, Didymoteicho – 3 November 1254, Nymphaion), was Emperor of Nicaea from 1222 to 1254. He was succeeded by his son, known as Theodore II Laskaris.