"John III Doukas Vatatzes, Latinized as Ducas Vatatzes (Greek: Ιωάννης Δούκας Βατάτζης, Iōannēs 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." - (en.wikipedia.org 11.08.2021)
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