| Millennium: | 1st millennium |
|---|---|
| Centuries: | |
| Decades: | |
| Years: |
|
| Gregorian calendar | 821 DCCCXXI |
| Ab urbe condita | 1574 |
| Armenian calendar | 270 ԹՎ ՄՀ |
| Assyrian calendar | 5571 |
| Balinese saka calendar | 742–743 |
| Bengali calendar | 228 |
| Berber calendar | 1771 |
| Buddhist calendar | 1365 |
| Burmese calendar | 183 |
| Byzantine calendar | 6329–6330 |
| Chinese calendar | 庚子年 (Metal Rat) 3517 or 3457 — to — 辛丑年 (Metal Ox) 3518 or 3458 |
| Coptic calendar | 537–538 |
| Discordian calendar | 1987 |
| Ethiopian calendar | 813–814 |
| Hebrew calendar | 4581–4582 |
| Hindu calendars | |
| - Vikram Samvat | 877–878 |
| - Shaka Samvat | 742–743 |
| - Kali Yuga | 3921–3922 |
| Holocene calendar | 10821 |
| Iranian calendar | 199–200 |
| Islamic calendar | 205–206 |
| Japanese calendar | Kōnin 12 (弘仁１２年) |
| Javanese calendar | 717–718 |
| Julian calendar | 821 DCCCXXI |
| Korean calendar | 3154 |
| Minguo calendar | 1091 before ROC 民前1091年 |
| Nanakshahi calendar | −647 |
| Seleucid era | 1132/1133 AG |
| Thai solar calendar | 1363–1364 |
| Tibetan calendar | 阳金鼠年 (male Iron-Rat) 947 or 566 or −206 — to — 阴金牛年 (female Iron-Ox) 948 or 567 or −205 |
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Thomas the Slav captures cities in Anatolia
Year 821 (DCCCXXI) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar.
Events
By place
Byzantine Empire
- Byzantine general Thomas the Slav leads a revolt and secures control over most of the Byzantine themes (provinces) in Anatolia. He gets recognition from the Abbasid Caliphate, and concludes a peace treaty with Caliph al-Ma'mun. Thomas crosses with his fleet from Abydos to Thrace, and blockades Emperor Michael II in Constantinople; but Thomas' first attack on the capital fails.
Europe
- February – Duke Borna of Croatia dies after an 11-year reign, as vassal of the Frankish Empire. He is succeeded by his nephew, Vladislav.[1] Emperor Louis I recognizes him as prince of Dalmatia and Liburnia, at the Council of Aachen.
- October – Lothair I, co-emperor and eldest son of Louis I, marries Ermengarde in Thionville (north-eastern France). She is the daughter of Count Hugh of Tours.
Britain
- King Coenwulf of Mercia dies in Basingwerk near Holywell (Wales), while preparing for another assault on Powys, and is buried in Winchcombe Abbey. He is briefly succeeded by his son Cynehelm, but he is killed, probably fighting the Welsh, though supposedly through the treachery of his sister Cwenthryth. The Mercian throne passes to Coenwulf's brother, Ceolwulf I.
Abbasid Caliphate
- Tahir ibn Husayn, an Iranian general, is appointed to govern Khurasan, as a reward for supporting the Abbasid caliph al-Ma'mun in the Fourth Fitna. This begins the rule of the Tahirid dynasty over Khurasan, which will last until 873.
Births
- Gao Pian, general of the Tang dynasty (d. 887)
- Gisela, Frankish princess, daughter of Louis the Pious
- Ibn Abi Asim, Muslim Sunni scholar (or 822)
- Ordoño I, king of Asturias (approximate date)
Deaths
- April 7 – George the Standard-Bearer, archbishop of Mytilene (b. c. 776)
- May 2 – Liu Zong, general of the Tang Dynasty
- December 18 – Theodulf, bishop of Orléans
- Arno, archbishop of Salzburg
- Artrí mac Cathail, king of Munster (Ireland)
- Benedict of Aniane, Frankish monk
- Borna, duke (knez) of Croatia
- Coenwulf, king of Mercia
- Egbert, bishop of Lindisfarne
- Guisclafred, Frankish nobleman (approximate date)
- Li Su, general of the Tang dynasty (b. 773)
- Tian Hongzheng, general of the Tang dynasty (b. 764)
- Wei Guanzhi, chancellor of the Tang dynasty (b. 760)
- Zheng Yuqing, chancellor of the Tang dynasty (b. 746)
References
- ^ Mladjov, Ian. "Croatian Rulers" (PDF). Retrieved May 21, 2011.