Nielsen Hayden genealogy
Descendants of Alexios III Komnenos Angelos, Emperor of Byzantium
Aft 1155 - Aft 1211 (> 56 years)Father: Andronikos Doukas Angelos (Abt 1122 - Aft 1185)
Mother: Euphrosyne Kastamonitissa (Abt 1125 - Aft 1195)
Alexios III Komnenos Angelos, Emperor of Byzantium (Aft 1155 - Aft 1211)
Euphrosyne Doukaina Kamaterina (Abt 1155 - Between 1210 and 1211)(m. 1169)
   └─ Anna Komnena Angelina (Abt 1174 - 1212)
    Theodoros I Komnenos Laskaris, Emperor in Nicea (Abt 1175 - Aug 1222)(m. 1199)
       ├─ Eirene Doukaina Komnene Laskarina (Abt 1200 - 1239)
       │ Ioannes III Doukas, Emperor of Nicaea (Abt 1192 - 3 Nov 1254 Nymphaion, now Kemelpasa, Izmir, Turkey)
       │ (m. 1212)
       │ (m. 1212)
       │    └─ Theodoros II Doukas Laskaris, Emperor of Nicaea (1222 - Aug 1258) =>
       │     + Elena of Bulgaria & Vlachia (1224 - Bef 1254)(m. 1235)
       └─ Maria Laskarina (Abt 1206 of Nicea, Anatolia - 1270)
        Béla IV, King of Hungary (1206 - 3 May 1270)(m. Abt 1218)
           │ + Leo Danilowitsch, King of Halicz (Abt 1228 - 1301)(m. Between 1251 and 1252)
           │ + Rosztiszlo, King of Bulgaria; Grand Duke of Kiev (Between 1212 and 1225 - Abt 1264)(m. 1244)
           ├─ Istvan V, King of Hungary (Dec 1239 - 1 Aug 1272) =>
           │ + Erszebet of Kumania ( - Aft 1290)
           └─ Helene of Hungary (Abt 1244 Esztergom, Hungary - 6 Mar 1298 Gniezno, Poland) =>
            + Boleslaw (1221 - 7 Apr 1279)(m. 1257)