About 830 an Arabian dhow sinks on its journey from China to Arabia near the Indonesian island of Belitung, carrying some 60,000 trade items, the largest collection of Tang dynasty artifacts outside of China (Belitung shipwreck).
Fall – Muslim Arabs reinvade Sicily, and lay siegetoPalermo. Symeon, Byzantine commander of the imperial bodyguard (spatharios), surrenders the city in exchange for a safe departure.
AnUyghurTurk sues the son of a Chinese general, who had failed to repay a debt of 11 million government-issued copper coins. Emperor Wenzong hears the news, and is so upset that he not only banishes the general, but attempts to ban all trade between Chinese and foreigners except for goods and livestock. This ban is unsuccessful, and trade with foreigners resumes, especially in maritime affairs overseas.
Mojmir I, Moravian duke, expels Prince Pribina from his homeland (western part of modern Slovakia). He unifies Great Moravia and becomes the first known ruler of the Moravian Slavs, who founds the House of Mojmir (approximate date).
December 14 – Sweet Dew Incident: Emperor Wenzong of Tang plots to free the court from the influence of his palace eunuchs. In the northeast sector of the capital, Chang'an, after the failure of the emperor's chancellor Li Zhongyan to subdue the eunuchs' influence, troops under the eunuchs' command slaughter many officials and other associates.
Driven by tensions between his favoured Turkish guard and the populace of Baghdad, Abbasidcaliphal-Mu'tasim moves his residence to the new city of Samarra, 130 km north of Baghdad. With brief interruptions, the city will remain the seat of the Abbasid caliphs until 892.
Malamir, ruler (khan) of the Bulgarian Empire, dies after a 4-year reign and is succeeded by his nephew Presian I. Because of his young age and inexperience, the Bulgarian state affairs are dominated by his minister and commander-in-chief Isbul.
July 22 – Battle of Anzen: Caliph al-Mu'tasim launches a major punitive expedition against the Byzantine Empire, targeting the two major Byzantine fortress cities of central Anatolia (Ancyra and Amorium). He mobilises a vast army (80,000 men) at Tarsus, which is divided into two main forces. The northern force, under commander al-Afshin, invades the Armeniac Theme from the region of Melitene, joining up with the forces of the city's emir, Umar al-Aqta. The southern, main force, under al-Mu'tasim, passes the Cilician Gates into Cappadocia. Emperor Theophilos attacks the Abbasids, inflicting 3,000 casualties, but is heavily defeated by a counter-attack of 10,000 Turkish mounted archers. Theophilos and his guard are encircled, and barely manage to break through and escape.[14][15][16]
August – Siege of Amorium: The Abbasids besiege the Byzantine fortress city of Amorium, which is protected by 44 towers, according to the contemporary geographer Ibn Khordadbeh. Both besiegers and besieged have many siege engines, and for several days both sides exchange missile fire. However, a Muslim prisoner defects to al-Mu'tasim, and informs him about a place in the wall which has been badly damaged by heavy rainfall. The Abbasids concentrate their hits on this section, and after two days manage to breach the city wall. After two weeks of repeated attacks, the Byzantine defenders surrender. The city is sacked and plundered, 70,000 inhabitants are slaughtered, and the survivors are sold as slaves.
Miniature from the Madrid Skylitzes depicting the Arab siege of Amorium in 838
January – Babak Khorramdin, an Iranian military leader, is brutally executed by order of al-Mu'tasim.[19]
A conspiracy is discovered, led by General Ujayf ibn Anbasa, to assassinate al-Mu'tasim while he is campaigning, and place his nephew Al-Abbas ibn al-Ma'mun on the throne. A widespread purge of the army follows, which cements the leading role of the Turkish slave-soldiers (ghilman) in the Abbasid military establishment. Ujayf is executed and Al-Abbas put in prison, where he dies.
The Yazidis rise up against the Abbasids (approximate date).[20]
^M. Th. Houtsma, 1993, E. J. Brill's First Encyclopaedia of Islam, 1913-1936: Volume 4 - p. 1136, Brill.
^Kreutz, Barbara M (1991). Before the Normans: Southern Italy in the Ninth and Tenth Centuries, p. 23 (University of Pennsylvania, Press: Philadelphia).
^Bóna, István (2000). The Hungarians and Europe in the 9th-10th centuries. Budapest: Historia - MTA Történettudományi Intézete, p. 11. ISBN963-8312-67-X.
