820

820 in various calendars
Gregorian calendar	820; DCCCXX
Ab urbe condita	1573
Armenian calendar	269; ԹՎ ՄԿԹ
Assyrian calendar	5570
Balinese saka calendar	741–742
Bengali calendar	227
Berber calendar	1770
Buddhist calendar	1364
Burmese calendar	182
Byzantine calendar	6328–6329
Chinese calendar	己亥年 (Earth Pig); 3517 or 3310; — to —; 庚子年 (Metal Rat); 3518 or 3311
Coptic calendar	536–537
Discordian calendar	1986
Ethiopian calendar	812–813
Hebrew calendar	4580–4581
Hindu calendars
- Vikram Samvat	876–877
- Shaka Samvat	741–742
- Kali Yuga	3920–3921
Holocene calendar	10820
Iranian calendar	198–199
Islamic calendar	204–205
Japanese calendar	Kōnin 11; (弘仁１１年)
Javanese calendar	716–717
Julian calendar	820; DCCCXX
Korean calendar	3153
Minguo calendar	1092 before ROC; 民前1092年
Nanakshahi calendar	−648
Seleucid era	1131/1132 AG
Thai solar calendar	1362–1363
Tibetan calendar	阴土猪年; (female Earth-Pig); 946 or 565 or −207; — to —; 阳金鼠年; (male Iron-Rat); 947 or 566 or −206

Millennium:	1st millennium
Centuries:	8th century; 9th century ; 10th century;
Decades:	800s; 810s; 820s ; 830s; 840s;
Years:	817; 818; 819; 820 ; 821; 822; 823;

Year 820 (DCCCXX) was a leap year starting on Sunday (link will display the full calendar) of the Julian calendar.

Events

Abbasid caliph Al-Ma'mun appointed Isa ibn Yazid al-Juludi as Abbasid governor of Yemen for few months.
Caliph Al-Ma'mun appointed Hisn ibn al-Minhal as Abbasid governor of Yemen for few months.
Caliph Al-Ma'mun appointed Ibrahim al-Ifriqi as Abbasid governor of Yemen. He remained in office until 821.
Caliph al-Ma'mun appointed Abu Nasr ibn al-Sari as Abbasid governor of Egypt.

December 25 – Emperor Leo V (the Armenian) is assassinated by conspirators in the Hagia Sophia, at Constantinople. Though unarmed, he fights back fiercely but dies of his wounds. He is succeeded by Michael II, the commander of the palace guard (excubitores). Leo's family (including his mother and his wife Theodosia) are exiled to monasteries in Princes' Islands.^[1]

Fedelmid mac Crimthainn assumes the kingship as ruler of Munster (modern Ireland).

Emperor Xian Zong dies from poisoning (due to medicines), after a 14-year reign. He is succeeded by his son Mu Zong, as ruler of the Tang dynasty.

^ Theophanes Continuatus, pp. 40–41.
^ Lynch, Michael, ed. (February 24, 2011). The Oxford companion to Scottish history. Oxford University Press. p. 70. ISBN 9780199693054.

Gregorian calendar	820 DCCCXX
Ab urbe condita	1573
Armenian calendar	269 ԹՎ ՄԿԹ
Assyrian calendar	5570
Balinese saka calendar	741–742
Bengali calendar	227
Berber calendar	1770
Buddhist calendar	1364
Burmese calendar	182
Byzantine calendar	6328–6329
Chinese calendar	己亥年 (Earth Pig) 3517 or 3310 — to — 庚子年 (Metal Rat) 3518 or 3311
Coptic calendar	536–537
Discordian calendar	1986
Ethiopian calendar	812–813
Hebrew calendar	4580–4581
Hindu calendars
- Vikram Samvat	876–877
- Shaka Samvat	741–742
- Kali Yuga	3920–3921
Holocene calendar	10820
Iranian calendar	198–199
Islamic calendar	204–205
Japanese calendar	Kōnin 11 (弘仁１１年)
Javanese calendar	716–717
Julian calendar	820 DCCCXX
Korean calendar	3153
Minguo calendar	1092 before ROC 民前1092年
Nanakshahi calendar	−648
Seleucid era	1131/1132 AG
Thai solar calendar	1362–1363
Tibetan calendar	阴土猪年 (female Earth-Pig) 946 or 565 or −207 — to — 阳金鼠年 (male Iron-Rat) 947 or 566 or −206