List of state leaders in 823

Asia

*Bohai/Balhae - Da Renxiu/Dae In-su, King of Bohai/Balhae (818?-830)
*China (Tang Dynasty) - Muzong, Emperor of Tang China (821-824)
*Gurjara - Nagabhata II, Pratihara King of Gurjara (805-833)
*Japan (Heian Period) -
*#Emperor Saga, Emperor of Japan (809-823)
*#Emperor Junna, Emperor of Japan (823-833)
*Silla - Heondeok, King of Silla (809-826)

Europe

*Aragon - García I Galíndez - Count of Aragon (820-833)
*Asturias - Alfonso II, King of Asturias (791-842)
*Bulgaria - Omortag, Khan of the Bulgars (815-831)
*Byzantine Empire - Michael II. Roman Emperor (820-829)
*Cordoba - Abd-ar-rahman II, Emir of Cordoba (822-852)
*Dál Riata - Óengus, King of Dalriada (820–834)
*Franks - Louis the Pious, King of the Franks and Holy Roman Emperor (814-840)
**Aquitaine - Pippin I, King of Aquitaine (817-838)
**Barcelona - Rampó, Count of Barcelona (820-825)
**Bavaria - Louis the German, King of Bavaria (817-876)
**Dalmatian Croats - Vladislav, Duke of the Dalmatian Croats (c.821-835)
**Gascony - Aznar I Galíndez, [Duke of Gascony (820-839)
**Italy - Lothair I, King of Italy (817-839)
**Poitiers -
***Renaud, Count of Poitiers (795-843
***Bernard I, Count of Poitiers (815-844)
**Toulouse - Bérenger le Sage, Duke of Toulouse (814-835)
**Urgell - Aznar I Galíndez, Count of Urgell (820-839)
*Gwynedd - Hywel "Farf-Fehinog" ab Caradog
*Ireland - Conchobar mac Donnchada, High King of Ireland (818-831)
**Ailech - Aed Oirdnide mac Neill, King of Ailech (788-819)
**Connacht - ?
**Hy-Many - ?
**Leinster - Muiredach mac Ruaidri, King of Leinster (808-829)
**Mide - Conchobar mac Donnchado, King of Mide (803-833)
**Ulaid - ?
*Kartli - Ashot I Kurapalate, Prince of Kartli (809-826)
*Kent - Baldred, King of Kent (c.823?-825)
*Mercia -
*#Ceolwulf I, King of Mercia (821–823)& King of Kent (c.821?-823)
*#Beornwulf, King of Mercia (823–826)
**Essex - Sigered, Duke of Essex (812-825)
*Northumbria - Eanred, King of Northumbria (810-841)
*Pannonian Croats - Ljudevit Posavski, Duke of the Pannonian Croats (c.810-823)
*Papal States - Paschal I, Pope of the Roman Catholic Church (817-824)
*Strathclyde - Artgal, King of Strathclyde (816-872)
*Venice - Angelo Participazio, Doge of Venice (809-827)
*Wessex - Egbert, King of Wessex (802-839)