John III Doukas Vatatzes, Latinized as Ducas Vatatzes, was Emperor of Nicaea from 1221 to 1254. He was succeeded by his son, known as Theodore II Doukas Laskaris.
- Occupation
- sovereign
- Position held
- Emperor of Nicaea
- Citizenship
- Byzantine Empire
- Born
- 1192
- Died
- November 3, 1254, 1254