List of state leaders in 856

855 state leaders - Events of 856 - 857 state leaders - State leaders by year----

Asia

*Bohai/Balhae - Da Yizhen/Dae I-jin, King of Bohai/Balhae (830-857)
*China (Tang Dynasty) - Xuanzong, Emperor of Tang China (846-859)
*Gurjara - Mihira Bhoja I, Pratihara King of Gurjara (c. 836-886)
*Japan (Heian Period) - Emperor Montoku, emperor of Japan (850-858)
*Silla - Munseong, King of Silla (839-857)

Europe

*Asturias - Ordoño I, King of Asturias (850-866)
*Benevento- Adelchi, Duke of Benevento (853-878)
*Brittany - Nominoe, King of the Bretons (841-851)
*Bulgaria - Boris I, Khan of Bulgaria (852-889)
*Cordoba - Muhammad I, Emir of Cordoba (852-886)
*Eastern Francia - Louis II, King of Eastern Francia (817-876)
*East Anglia¹ - Edmund, King of East Anglia (855–870)
*England -
*#Æthelwulf of Wessex, Bretwalda (839–856)
*#Æthelbald of Wessex, Bretwalda (856–860)
*Friesland - Rorik, King of the Danish Vikings in Friesland (850-880)
*Mercia - Burgred, King of Mercia (852–874)
*Northumbria¹ - Osbert, King of Northumbria (849–867)
*Ireland -
**Bard of Limerick, High King of Ireland (845–880)
**Mael Seachlainn I, High King of Ireland (845–860)
*Lotharingia - Lothair I, King of Middle Francia (840-855)
*Scotland - Kenneth I, King of Scots and Picts (843–858)
*Strathclyde - Arthgal f Dyfnwal, King of Strathclyde (816–872)
*Venice - Pietro Tradonico, Doge of Venice (837-864)
*Wales - Rhodri "Mawr" ap Merfyn, King of Gwynedd (844–878)
*Western Francia - Charles the Bald, King of Western Francia (843-877)

Middle East

*Abbasid Caliphate - Al-Mutawakkil, Abbasid Caliph (847-861)
*Byzantine Empire - Michael III, Byzantine Emperor (842-867)

Notes

#Though East Anglia, Northumbria and Mercia are traditionally perceived to have been in the heptarchy they were largely independent kingdoms until its conquest by the Danes in 869 and 867, respectively - where Mercia was conquered by Wessex in 874. All other members of the heptarchy had been conquered by Wessex and by this time had no form or king.