Theodor I.
Theodor I. is the name of the following people:
- Theodor I (Pope) († 649), Pope
- Theodore I (Jerusalem) , Patriarch of Jerusalem
- Theodor I (Patriarch) , Patriarch of Constantinople
- Theodor I of Rostov (~ 992 - ~ 1010), first bishop of Rostov
- Theodor I (Byzantium) (~ 1174–1222), Emperor of Byzantium
- Theodor I. (Morea) (1355-1407), ( Theodōros I. Palaiologos ), Byzantine despot
- Theodor I († 1414), Emperor of Ethiopia, see Tewodros I.
- Theodor I (1694–1756), King of Corsica, see Theodor von Neuhoff