List of state leaders in 818

This is a list of heads of state, government leaders, and other rulers in the year 818.

Asia

• China (Tang dynasty) – Emperor Xianzong (806–820)
• Pratihara Empire – Nagabhata II (805–833)
• Japan (Heian period) – Emperor Saga (809–823)
• Korea (North South States Period)
  • Balhae –
    1. Gan (817–818)
    2. Seon (818–830)
  • Unified Silla – Heondeok (809–826)

Europe

• First Bulgarian Empire – Omurtag, Khan of the Bulgars (814–831)
• Byzantine Empire – Leo V the Armenian (813–820)
• Caucasus
  • Principality of Iberia – Ashot I Kuropalates (c. 813–830)
  • Principality of Kakheti – Grigol (786–827)
• Kingdom of Denmark – Horik I (813–854)
• England (Heptarchy) – Coenwulf of Mercia, Bretwalda (796–821)
  • Kingdom of Essex – Sigered (812–825)
  • Kingdom of Mercia – Coenwulf, King of Mercia (796–821) and East Anglia (c.799–821) and King of Kent (807–821)
  • Kingdom of Northumbria – Eanred (810–841)
  • Kingdom of Wessex – Egbert (802–839)
• Frankish Empire –
  • Louis the Pious, King of the Franks and senior Holy Roman Emperor (814–840)
  • Lothair I, King of Italy and junior Holy Roman Emperor (817–855)
  • Kingdom of Aquitaine – Pepin I of Aquitaine (817–838)
    • Duchy of Gascony –
      1. Gassia I Semen (816–818)
      2. Lupo III Centule of Gascony (818–819)
    • County of Toulouse – Berengar the Wise (816–835)
  • County of Barcelona – Berà (801–820)
  • Duchy of Bavaria – Louis the German (817–843)
  • Duchy of Croatia – Borna of Croatia (c.810–821)
  • County of Nantes – Lambert I (818–831)
  • County of Urgell – Borell (798–820)
• Ireland – Áed Oirdnide, High King of Ireland (797–819)
  • Kingdom of Ailech – Áed Oirdnide (788–819)
  • Kingdom of Connacht – Diarmait mac Tommaltaig (815–833)
  • Uí Maine –
  • Kingdom of Leinster –
    • Muiredach mac Brain, co-King of Leinster (808–818)
    • Muiredach mac Ruadrach, co-King of Leinster (808–829)
  • Kingdom of Mide – Conchobar mac Donnchada (803–833)
  • Kingdom of Ulaid – Cairell mac Fiachnai (810–819)
• Italy -
  1. Bernard, King of Italy (810–818)
  2. Lothair I, King of Italy and junior Holy Roman Emperor (818–855)
  • Principality of Benevento – Sico of Benevento (817–832)
  • Papal States – Pope Paschal I (817–824)
  • Republic of Venice – Agnello Participazio, Doge of Venice (811–827)
• Pannonian Croatia – Ljudevit Posavski (c.810–823)
• Scotland
  • Kingdom of the Picts – Causantín mac Fergusa (787–820)
• Spain –
  • County of Aragon – Aznar Galíndez I (809–820)
  • Kingdom of Asturias – Alfonso II (791–842)
  • Emirate of Córdoba – al-Hakam I (796–822)
• Wales –
  • Kingdom of Gwynedd – Hywel ap Rhodri Molwynog (816–825)
  • Kingdom of Powys – Cyngen ap Cadell (808–855)

Middle East

• Abbasid Caliphate – Al-Ma'mun (813–833)
• Byzantine Empire – Leo V the Armenian (813–820)