List of state leaders in 828

827 state leaders – Events of 828 – 829 state leaders – State leaders by year

Africa

• Ifriqiya (Aghlabids) - Ziyadat Allah I, Emir (817–838)

Asia

• China (Tang Dynasty) - Wenzong, Emperor of Tang China (826–840)
• Gurjara - Nagabhata II, Pratihara King of Gurjara (805–833)
• Japan (Heian Period) - Emperor Junna, Emperor of Japan (823–833)
• Korea (North South States Period)
  • Balhae - Seon, King of Balhae(818–830)
  • Silla - Heungdeok, King of Silla (826–836)

Europe

• Bulgaria - Omurtag, Khan of the Bulgars (814–831)
• Byzantine Empire - Michael II (820–829)
• Caucasus
  • Principate of Iberia - Ashot I Kuropalates (c. 813–830)
  • Principality of Kakheti - Vache, Prince of Kakheti (827–839)
• Kingdom of Denmark - Horik I (813–854)
• England (Heptarchy) -
  • Kingdom of East Anglia - Æthelstan (826–c. 839)
  • Mercia - Wiglaf, King of Mercia (827–829)
  • Northumbria - Eanred, King of Northumbria (810–841)
  • Wessex - Egbert, King of Wessex (802–839) and King of Kent (825–839)
• 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)
  • Aquitaine - Pepin I of Aquitaine, King of Aquitaine (817–838)
    • Auvergne - Guerin of Provence, Count of Auvergne (819–839)
    • Gascony - Aznar Sánchez, Duke of Gascony (819–836)
    • Toulouse - Berengar the Wise, Count of Toulouse (816–835)
  • County of Barcelona - Bernat of Septimania (826–832)
  • Bavaria - Louis the German, King of Bavaria (817–843)
  • Littoral Croatia - Vladislav of Croatia, Duke of Littoral Croatia (c. 821–835)
  • County of Nantes - Lambert I (818–831)
  • Poitiers - Emenon, Count of Poitiers (828–839)
  • County of Urgell - Aznar I Galíndez (820–834)
• Ireland - Conchobar mac Donnchada, High King of Ireland (819–833)
  • Ailech - Niall Caille, King of Ailech (823–846)
  • Connacht - Diarmait mac Tommaltaig, King of Connacht (815–833)
  • Uí Maine -
  • Leinster - Muiredach mac Ruadrach, King of Leinster (808–829)
  • Kingdom of Mide - Conchobar mac Donnchado (803–833)
  • Ulaid - Muiredach mac Eochada, King of Ulaid (825–839)
• Italy - Lothair I, King of Italy and Junior Holy Roman Emperor (818–855)
  • Principality of Benevento - Sico of Benevento (817–832)
  • Papal States - Pope Gregory IV (827–844)
  • Republic of Venice - Giustiniano Participazio, Doge of Venice (827–829)
• Scotland
  • Picts - Óengus, King of the Picts (820–834)
• Spain -
  • County of Aragon - García Galíndez (820–833)
  • Kingdom of Asturias - Alfonso II (791–842)
  • Caliphate of Córdoba - Abd-ar-rahman II (822–852)
  • Kingdom of Pamplona - Iñigo Arista (824–851/852)
• Wales -
  • Kingdom of Gwynedd - Merfyn Frych (825–844)
  • Kingdom of Powys - Cyngen ap Cadell (808–855)

Middle East

• Abbasid Caliphate - Al-Ma'mun, Caliph (813–833)
• Byzantine Empire - Michael II (820–829)