|821 by topic|
|Ab urbe condita||1574|
|Balinese saka calendar||742–743|
|Chinese calendar|| 庚子年 (Metal Rat)|
3517 or 3457
— to —
辛丑年 (Metal Ox)
3518 or 3458
|- Vikram Samvat||877–878|
|- Shaka Samvat||742–743|
|- Kali Yuga||3921–3922|
|Japanese calendar|| Kōnin 12|
|Minguo calendar||1091 before ROC |
|Seleucid era||1132/1133 AG|
|Thai solar calendar||1363–1364|
947 or 566 or −206
— to —
948 or 567 or −205
|Wikimedia Commons has media related to 821 .|
[[File:MadridSkylitzesFol30vDetail.jpg|upright=1.4|thumb|right|Thomas the Slav captures cities in Anatoliahigesff] Year 821 ( DCCCXXI ) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar.
Thomas the Slav was a 9th-century Byzantine military commander, most notable for leading a wide-scale revolt in 821–23 against Emperor Michael II the Amorian.
The numeric system represented by Roman numerals originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers in this system are represented by combinations of letters from the Latin alphabet. Roman numerals, as used today, employ seven symbols, each with a fixed integer value, as follows:
A common year starting on Tuesday is any non-leap year that begins on Tuesday, 1 January, and ends on Tuesday, 31 December. Its dominical letter hence is F. The current year, 2019, is a common year starting on Tuesday in the Gregorian calendar. The last such year was 2013 and the next such year will be 2030, or, likewise, 2014 and 2025 in the obsolete Julian calendar, see below for more. Any common year that starts on Sunday, Monday or Tuesday has two Friday the 13ths. This common year contains two Friday the 13ths in September and December. Leap years starting on Monday share this characteristic. From July of the year that precedes this year until September in this type of year is the longest period that occurs without a Friday the 13th. Leap years starting on Saturday share this characteristic, from August of the common year that precedes it to October in that type of year.
The themes or themata were the main military/administrative divisions of the middle Byzantine Empire. They were established in the mid-7th century in the aftermath of the Slavic invasion of the Balkans and Muslim conquests of parts of Byzantine territory, and replaced the earlier provincial system established by Diocletian and Constantine the Great. In their origin, the first themes were created from the areas of encampment of the field armies of the East Roman army, and their names corresponded to the military units that had existed in those areas. The theme system reached its apogee in the 9th and 10th centuries, as older themes were split up and the conquest of territory resulted in the creation of new ones. The original theme system underwent significant changes in the 11th and 12th centuries, but the term remained in use as a provincial and financial circumscription until the very end of the Empire.
Anatolia, also known as Asia Minor, Asian Turkey, the Anatolian peninsula, or the Anatolian plateau, is the westernmost protrusion of Asia, which makes up the majority of modern-day Turkey. The region is bounded by the Black Sea to the north, the Mediterranean Sea to the south, the Armenian Highlands to the east, and the Aegean Sea to the west. The Sea of Marmara forms a connection between the Black and Aegean Seas through the Bosphorus and Dardanelles straits and separates Anatolia from Thrace on the European mainland.
The Abbasid Caliphate was the third of the Islamic caliphates to succeed the Islamic prophet Muhammad. It was founded by a dynasty descended from Muhammad's uncle, Abbas ibn Abdul-Muttalib, from whom the dynasty takes its name. They ruled as caliphs for most of the caliphate from their capital in Baghdad in modern-day Iraq, after having overthrown the Umayyad Caliphate in the Abbasid Revolution of 750 CE (132 AH).
A vassal is a person regarded as having a mutual obligation to a lord or monarch, in the context of the feudal system in medieval Europe. The obligations often included military support by knights in exchange for certain privileges, usually including land held as a tenant or fief. The term is applied to similar arrangements in other feudal societies.
Francia, also called the Kingdom of the Franks, or Frankish Empire was the largest post-Roman barbarian kingdom in Western Europe. It was ruled by the Franks during Late Antiquity and the Early Middle Ages. It is the predecessor of the modern states of France and Germany. After the Treaty of Verdun in 843, West Francia became the predecessor of France, and East Francia became that of Germany. Francia was among the last surviving Germanic kingdoms from the Migration Period era before its partition in 843.
Dalmatia is one of the four historical regions of Croatia, alongside Croatia proper, Slavonia and Istria.
Coenwulf was the King of Mercia from December 796 until his death in 821. He was a descendant of a sibling of King Penda, who had ruled Mercia in the middle of the 7th century. He succeeded Ecgfrith, the son of Offa; Ecgfrith only reigned for five months, and Coenwulf ascended the throne in the same year that Offa died. In the early years of Coenwulf's reign he had to deal with a revolt in Kent, which had been under Offa's control. Eadberht Præn returned from exile in Francia to claim the Kentish throne, and Coenwulf was forced to wait for papal support before he could intervene. When Pope Leo III agreed to anathematize Eadberht, Coenwulf invaded and retook the kingdom; Eadberht was taken prisoner, was blinded, and had his hands cut off. Coenwulf also appears to have lost control of the kingdom of East Anglia during the early part of his reign, as an independent coinage appears under King Eadwald. Coenwulf's coinage reappears in 805, indicating that the kingdom was again under Mercian control. Several campaigns of Coenwulf's against the Welsh are recorded, but only one conflict with Northumbria, in 801, though it is likely that Coenwulf continued to support the opponents of the Northumbrian king Eardwulf.
Basingwerk Abbey is a Grade I listed ruined abbey near Holywell, Flintshire, Wales. The abbey, which was founded in the 12th century, belonged to the Order of Cistercians. It maintained significant lands in the English county of Derbyshire. The abbey was abandoned and its assets sold following the Dissolution of the Monasteries in 1536.
Holywell is the fifth largest town and a community in Flintshire, Wales. It lies to the west of the estuary of the River Dee. The community includes Greenfield.
Ṭāhir ibn Ḥusayn, also known as Dhul-Yamīnayn, and al-Aʿwar, was an Iranian general and governor during the Abbasid caliphate. Specifically, he served under al-Ma'mun during the Fourth Fitna and led the armies that would defeat al-Amin, making al-Ma'mun the caliph. He was then rewarded as governor of Khorasan, which marked the beginning of the Tahirid dynasty.
The Iranian peoples, or the Iranic peoples, are a diverse Indo-European ethno-linguistic group that comprise the speakers of the Iranian languages.
Khorasan, sometimes called Greater Khorasan, is a historical region lying in northeast of Greater Persia, including part of Central Asia and Afghanistan. The name simply means "East, Orient" and loosely includes the territory of the Sasanian Empire north-east of Persia proper. Early Islamic usage often regarded everywhere east of so-called Jibal or what was subsequently termed 'Iraq Ajami', as being included in a vast and loosely-defined region of Khorasan, which might even extend to the Indus Valley and Sindh. During the Islamic period, Khorasan along with Persian Iraq were two important territories. The boundary between these two was the region surrounding the cities of Gurgan and Qumis. In particular, the Ghaznavids, Seljuqs and Timurids divided their empires into Iraqi and Khorasani regions.
Gao Pian, courtesy name Qianli (千里), formally the Prince of Bohai (渤海王), was a general of the Chinese dynasty Tang Dynasty. He initially gained renown for defeating Dali incursions, but later became known for his failure to repel the rebel army under Huang Chao and his mismanagement of Huainan Circuit, which he governed as military governor (Jiedushi). A rebellion against him in 887 resulted in intense internal warfare in Huainan Circuit and his imprisonment by Qin Yan, who eventually put him to death.
The Tang dynasty or the Tang Empire was an imperial dynasty of China, preceded by the Sui dynasty and followed by the Five Dynasties and Ten Kingdoms period. Historians generally regard the Tang as a high point in Chinese civilization, and a golden age of cosmopolitan culture. Tang territory, acquired through the military campaigns of its early rulers, rivaled that of the Han dynasty. The Tang capital at Chang'an was the most populous city in the world in its day.
Year 887 (DCCCLXXXVII) was a common year starting on Sunday of the Julian calendar.
The 800s decade ran from January 1, 800, to December 31, 809.
The 810s decade ran from January 1, 810, to December 31, 819.
The 820s decade ran from January 1, 820, to December 31, 829.
Year 840 (DCCCXL) was a leap year starting on Thursday of the Julian calendar.
Year 827 (DCCCXXVII) was a common year starting on Tuesday of the Julian calendar.
Year 847 (DCCCXLVII) was a common year starting on Saturday of the Julian calendar.
Year 812 (DCCCXII) was a leap year starting on Thursday of the Julian calendar.
Year 785 (DCCLXXXV) was a common year starting on Saturday of the Julian calendar. The article denomination 785 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. It is still used today in this manner.
Year 796 (DCCXCVI) was a leap year starting on Friday of the Julian calendar. The denomination 796 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 818 (DCCCXVIII) was a common year starting on Friday of the Julian calendar.
Year 819 (DCCCXIX) was a common year starting on Saturday of the Julian calendar.
Year 822 (DCCCXXII) was a common year starting on Wednesday of the Julian calendar.
Year 832 (DCCCXXXII) was a leap year starting on Monday of the Julian calendar.
Year 833 (DCCCXXXIII) was a common year starting on Wednesday of the Julian calendar.
Year 865 (DCCCLXV) was a common year starting on Monday of the Julian calendar.
Year 866 (DCCCLXVI) was a common year starting on Tuesday of the Julian calendar.
Year 870 (DCCCLXX) was a common year starting on Sunday of the Julian calendar.
Year 873 (DCCCLXXIII) was a common year starting on Thursday of the Julian calendar.
Year 879 (DCCCLXXIX) was a common year starting on Thursday of the Julian calendar.
Year 905 (CMV) was a common year starting on Tuesday of the Julian calendar.