List of state leaders in 900

899 state leaders – Events of 900 – 901 state leaders – State leaders by year

Asia

• China (Tang Dynasty) – Zhaozong, Emperor of Tang China (888–904)
• Japan – Emperor Daigo, emperor of Japan (897–930)
• Korea (Later Three Kingdoms Period)
  • Balhae - Dae Wihae, King of Balhae (894–906)
  • Hubaekje – Gyeon Hwon, King of Hubaekje (900–935)
    • Hubaekje is founded by Gyeon Hwon
  • Silla – Hyogong, King of Silla (897–912)
• Khmer Empire – Yasovarman, King (899–910)

Europe

• Bulgaria - Simeon I, Knyaz of Bulgaria (893–927)
• Upper Burgundy - Rudolph I, King of Upper Burgundy (888–912)
• Byzantine Empire - Leo VI (886–912)
• Caucasus
  • Kingdom of Armenia - Smbat I (890–912)
  • Kingdom of Iberia - Adarnase IV (888–923)
  • Principality of Kakheti - Kvirike I, Prince of Kakheti (893–918)
  • Klarjeti -
    1. Bagrat I Mampali, Prince of Klarjeti (889–900)
    2. David Mampali (900–943)
• Littoral Croatia - Muncimir, Duke of Littoral Croatia (892–910)
• England (Heptarchy) -
  • Danelaw -
    • Kingdom of East Anglia - Eohric (890–902)
    • Northumbria - Æthelwold of Wessex, King of Northumbria (900–902)
  • Wessex - Edward the Elder, King of the Anglo-Saxons (899–924)
    • Mercia - Aethelred, Lord of the Mercians (c. 883–911)
• East Francia - Louis the Child, King of East Francia (899–911)
  • Bavaria - Luitpold, Margrave of Bavaria (895–907)
  • Duchy of Bohemia - Spytihněv I (894–915)
  • Lotharingia -
    1. Zwentibold, King of Lotharingia (895–900)
    2. Louis the Child, King of Lotharingia (900–911)
    • County of Frisia - Dirk I (c. 896–923)
    • County of Hainault - Sigard (898–908)
  • March of Pannonia - Aribo of Austria (871–909)
  • Duchy of Saxony - Otto the Illustrious (880–912)
  • Thuringia - Conrad, Duke of Thuringia (892–906)
• West Francia - Charles the Simple, King of West Francia (898–922)
  • County of Angoulême - Alduin I (886–916)
  • County of Anjou - Fulk I, Count of Anjou (898–942)
  • Aquitaine - William I, Duke of Aquitaine (893–918)
  • Duchy of Brittany - Alan I (876–907)
  • Duchy of Burgundy - Richard the Justiciar (898–921)
  • County of Flanders - Baldwin II (879–918)
  • County of Maine -
    1. Roger (895–900)
    2. Hugh I (900–950)
  • County of Paris - Robert I (888–923)
  • County of Toulouse - Odo (886–918)
  • Tours - Robert I, Count of Tours (888–922)
  • County of Vermandois - Herbert I (896–907)
• Gascony - Gassia II, Duke of Gascony (893–c. 930)
• Hungarian tribal federation - Árpád, Grand Prince of the Magyars (c. 895–c. 907)
• Ireland - Flann Sinna, High King of Ireland (879–916)
  • Ailech - Niall Glúndub, King of Ailech (896–919)
  • Connacht -
    1. Tadg mac Conchobair, King of Connacht (888–900)
    2. Cathal mac Conchobair, King of Connacht (900–925)
  • Uí Maine -
  • Leinster - Cerball mac Muirecáin, King of Leinster (885–909)
  • Kingdom of Mide - Flann Sinna (877–916)
  • Munster - Finguine Cenn nGécan mac Loégairi, King of Munster (895–902)
• Italy - Berengar, King of Italy (887–924), disputed by Louis the Blind, King of Italy (900–905)
  • Principality of Benevento -
    1. Radelchis II, Prince of Benevento (897–900)
    2. Atenulf I, Prince of Benevento (900–910)
  • County of Capua - Atenulf I (887–910)
  • Duchy of Gaeta - Docibilis I, Hypatus of Gaeta (866–906)
  • March of Ivrea - Anscar of Ivrea (888–902)
  • Duchy of Naples - Gregory IV (898–915)
  • Papal States -
    1. Pope John IX (898–900)
    2. Pope Benedict IV (900–903)
  • Principality of Salerno - Guaimar I (880–901)
  • Duchy of Spoleto - Alberic I (897–922)
  • March of Tuscany - Adalbert II (886–915)
  • Republic of Venice - Pietro Tribuno, Doge of Venice (887–912)
• Kievan Rus' - Oleg of Novgorod, Prince of Kiev (882–912)
• Great Moravia - Mojmír II, King of Great Moravia (894–906)
  • Principality of Nitra - Svatopluk II, Prince of Nitra (894–906)
• Norway - Harald I Fairhair, King of Norway (872–930)
• Novgorod - Oleg, Prince of Novgorod (879–912)
• Kingdom of Provence - Louis the Blind (887–928)
• Kingdom of Alba (Scotland) -
  1. Donald II (889–900)
  2. Constantine II (900–943)
• Serbia - Petar Gojniković, Knez of Serbia (892–917)
• Spain -
  • County of Aragon - Galindo Aznárez II (893–922)
  • Kingdom of Asturias - Alfonso III (866–910)
  • County of Barcelona - Wilfred II Borrel (897–911)
  • Caliphate of Córdoba - Abdallah ibn Muhammad (888–912)
  • County of Pallars - Raymond I (872–920)
  • Kingdom of Pamplona - Fortún Garcés (882–905)
  • County of Ribagorza - Raymond I (872–920)
• Wales -
  • Kingdom of Dyfed - Llywarch ap Hyfaidd (893–904)
  • Kingdom of Gwynedd - Anarawd ap Rhodri (878–916)
  • Kingdom of Powys -
    1. Merfyn ap Rhodri (878–900)
    2. Llywelyn ap Merfyn (900–942)
  • Kingdom of Seisyllwg - Cadell ap Rhodri (878–909)

Middle East

• Byzantine Empire – Leo VI (886–912)

Oceania

• Tonga – ʻAhoʻeitu, Tuʻi Tonga (c.900-?)