The 990s decade ran from January 1, 990, to December 31, 999.
- June 15 – Empress Theophanu dies of an illness at Nijmegen and is buried in the Church of Saint Pantaleon in Cologne. Empress Adelaide of Italy assumes regency over her grandson, the 10-year-old King Otto III.
- Al-Mansur, the de facto ruler of Al-Andalus, conquers the Castle of Montemor-o-Velho (modern Portugal). Expanding the Umayyad Caliphate of Córdoba.
- The city of Lund in Sweden is founded during the reign of the Danish king Sweyn Forkbeard (approximate date).
- The Ghana Empire takes the Berber town of Aoudaghost (modern Mauritania) as the West African nation makes further gains.
- Construction of the Al-Hakim Mosque by orders of the Fatimid vizier Gawar Al-Siqilli begins in Cairo (modern Egypt).
- June – The Pax Ecclesiae, an edict by the Catholic Church is promulgated. Held at three synods in different parts of southern and central France – at Charroux, Narbonne and Puy – attempting to outlaw acts of war against non-combatants and the clergy.
- Spring – Charles, duke of Lower Lorraine, is captured through the perfidy of Bishop Adalberon and is imprisoned by King Hugh I (Capet) in Orléans. Pope John XV appeals to Empress Adelaide of Italy, the grandmother and regent of the 11-year-old King Otto III to intervene. But occupied with rebellious Slavs and Bohemians, she declines.
- Spring – King Æthelred II (the Unready) signs an peace treaty with Richard I (the Fearless), duke of Normandy, which is ratified in Rouen. The English coast is threatened, Viking attacks ravage Kent and Sussex.
- August 11 – Battle of Maldon: The Anglo-Saxons under the Ealdorman Byrhtnoth are defeated by Norwegian Viking invaders, led by Olaf Tryggvason (later Olaf I of Norway) at Maldon (Northey Island) in Essex.
- Æthelred II decides to pay tribute (or Danegeld) to Olaf Tryggvason. He buys him off with a massive payment of 22,000 lbs of silver to hold off the Viking invaders and keep the peace in his realm.
- Spring – Fatimid troops under the defecting Hamdanid governor of Homs, Bakjur, attack Aleppo (modern Syria), but are defeated with Byzantine assistance. Bakjur is captured and executed by Emir Sa'd al-Dawla.
- Summer – Council of Reims: Archbishop Arnulf (illegitimate son of the late King Lothair III) is deposed for high treason (conspiring with his uncle Charles). He is succeeded by Gerbert of Aurillac.
- Spring – Pietro II Orseolo, doge of Venice, concludes a treaty with Emperor Basil II to transport Byzantine troops in exchange for commercial privileges in Constantinople. Venetian ships are exempted from customs duties at Abydos (mostly foreign goods are carried on Venetian ships). Venetian merchants in Constantinople are placed directly under the Grand Logothetes (Minister of Finance).
- May 25 – Mieszko I, prince (duke) of the Polans, dies after a reign of more than 30-years at Poznań. He is succeeded by his son Bolesław I (the Brave) who becomes ruler of Poland. Having inherited the principality (located between the Oder and the Warta rivers), Bolesław forms an alliance with the Holy Roman Empire.
- June 27 – Battle of Conquereuil: The Angevins under Fulk III (the Black) defeat the forces of Conan I, duke of Brittany, who is killed in the battle at Conquereuil (France).
- Norse Viking settlers establish a mint in Dublin (Ireland), to produce silver pennies (approximate date).
- Spring – The 12-year-old King Otto III gives the Sword of Saints Cosmas and Damian (also known as the Sword of Essen) as a gift to the convent in Essen. It symbolises the martyrdom of Cosmas and Damian, the patron saints of the city.
- Charles, duke of Lower Lorraine, dies in prison in Orléans (see 991). He is succeeded by his son Otto II, who inherits the full dukedom and pledges his allegiance to Otto III.
- July 4 – Pope John XV issues a decree canonizing the late Bishop Ulrich of Augsburg, the first recorded canonization of a saint.
- An increase in carbon-14 concentration, recorded in tree rings, suggests that a strong solar storm may have hit the Earth in either 993 or 994.
- September 15 – Battle of the Orontes: Fatimid forces under the Turkish general Manjutakin (also the governor of Damascus) besiege Apamea (modern Syria). Emperor Basil II sends a Byzantine expeditionary army led by Dux Michael Bourtzes to relieve the city in alliance with the Hamdanid Dynasty. In September the two armies meet on the Orontes River, Manjutakin defeats with his forces the Hamdanids and attacks the Byzantine force in the rear. The Byzantine army panicks and flees, losing some 5,000 men in the process.
- June 23 – Viking Age: Danish Viking raiders under (probably) King Sweyn Forkbeard plunder the city of Stade (Lower Saxony). Count Lothair Udo I is captured and killed during the battle with the pirates.
- September – King Otto III, now 14-year-old, receives at an assembly of the Imperial Diet in Solingen the regalia to rule the Kingdom of Germany. Otto appoints Heribert of Cologne as chancellor of Italy.
- A Danish Viking fleet under Olaf Tryggvason sails up the Thames Estuary and besiege London. King Æthelred II (the Unready) pays Olaf 16,000 lbs of silver (Danegeld).
- Olaf Tryggvason already a baptised Christian, is confirmed as Christian in a ceremony at Andover. After receiving gifts from Æthelred II, Olaf leaves for Norway.
- An increase in carbon-14 concentration, recorded in tree rings, suggests that a strong solar storm may have hit the Earth in either 993 or 994.
- Arab–Byzantine War: Emperor Basil II launches a counter-campaign against the Fatimid Caliphate. He leads an Byzantine expeditionary army (13,000 men) to aid the Hamdanid emir Sa'id al-Dawla – and crosses Asia Minor in only sixteen days. Basil lifts the siege of Aleppo and takes over the Orontes valley. He incorporates Syria into the Byzantine Empire – including the larger city of Antioch which is the seat of its eponymous Patriarch.
- King Eric VI (the Victorious) dies at Uppsala after a 25-year reign. He is succeeded by his son Olof Skötkonung as the first baptized ruler of Sweden.
- September 28 – Boleslaus II (the Pious), duke of Bohemia, storms Libice Castle and massacres the members of the Slavník Dynasty.
- Olaf Tryggvason is crowned king of Norway (until 1000) and builds the country's first Christian church.
- King Kenneth II is murdered at a banquet by Lady Finella in Fettercairn. He is succeeded by his nephew Constantine III (a son of the late King Cuilén) as ruler of Alba (Scotland).
- Uhtred (the Bold), a son of Ealdorman Waltheof I of Northumbria, establishes an episcopal see at Durham and moves the monastic community of Chester-le-Street there.
- Goryeo-Khitan War: Negotiations led by the Korean diplomat Seo Hui prevents a fullscale invasion of the Khitan-led Liao Dynasty. King Seongjong accepts Liao's demands – and agrees to end the alliance with the Chinese Song Dynasty. Goryeo becomes a Liao tributary state, the Khitan army (60,000 men) withdraws while Seongjong orders to strengthen the Korean border defenses.
- Spring – King Otto III starts his first expedition to Italy from Regensburg, and proceeds over the Brenner Pass. News of Otto's arrival prompt Crescentius II (the Younger), patrician (the de facto ruler) of Rome, to invite Pope John XV (exiled in Tuscany) back to Rome. Otto arrives in Verona and receives ambassadors of Doge Pietro II Orseolo of Venice.
- May 21 – The 16-year-old Otto III is crowned as Emperor of the Holy Roman Empire at the St. Peter's Basilica and claims also the title of King of Italy. His grandmother Adelaide, retires to a convent she has founded at Seltz (Alsace). Otto puts down a Roman rebellion, a number of nobles (including Crescentius II) are banished for their crimes.
- October 24 – King Hugh I (Capet) dies in Paris after a 9-year reign and is interred in the Basilica of St. Denis. He is succeeded by his 24-year-old son Robert II (the Pious) as king of France. Robert tries (during his reign) to increase his power, by pressing his claim of feudal lands that becomes vacant. This results in many territorial disputes.
- November 1 – Otto III grants the Bavarian bishopric of Freising 30 "royal hides" of land (about 800 hectares, or 20,000 acres - 800 hectares is 2,000 acres) in Neuhofen an der Ybbs (Lower Austria). An document (the oldest known) marks the first use of the name Ostarrîchi, meaning "Eastern Realm" (Austria in Old High German).
- November 20 – Richard I (the Fearless), duke of Normandy, dies after a 55-year reign. He is succeeded by his young son Richard II. During his minority, Rodulf of Ivry (his uncle), who wields the power as regent puts down a peasants revolt at the beginning of Richard's reign.
- October 14 – Caliph Al-Aziz Billah dies at Bilbeis in Egypt after a 21-year reign in which he has expanded his Shiite caliphate at the expense of the Byzantines, using Turkish mercenaries (Mamelukes). He is succeeded by his 11-year-old son Al-Hakim bi-Amr Allah as ruler of the Fatimid Caliphate (until 1021).
- Revolt of Tyre: The citizens of Tyre (modern Lebanon) revolt against the Fatimid Caliphate. Al-Hakim bi-Amr Allah sends a expeditionary army and navy to blockade the city by land and sea.
- The Niujie Mosque is constructed in Beijing during the Liao Dynasty. The first mosque is built under supervision of the Muslim architect Nazaruddin.
- April 1 – Pope John XV dies of fever after an 11-year reign. Meeting a Roman embassy at Ravenna, Otto appoints his cousin Bruno of Carinthia (a grandson of the late Emperor Otto I), who duly ascends as Gregory V. He becomes the 138th pope – and the first German pope of the Catholic Church.
- July 16 – Battle of Spercheios: Byzantine forces under General Nikephoros Ouranos defeat the Bulgarians at the Spercheios River in Greece. During a night battle the Bulgarian co-ruler Samuel is wounded, he and his son Gavril Radomir evade capture by feigning death among the bodies of their slain soldiers. Samuel sets off to Bulgaria and retreats with the remnants of his army into the Pindus Mountains. Ouranos returns to Constantinople, with 1,000 heads of Bulgarian soldiers and 12,000 captives.
- Al-Mansur, the de facto ruler of Al-Andalus, assaults and partially destroys the city of Santiago de Compostella. He is accompanied in his raid by Christian Portuguese lords, who all receive a share of the booty. On their way, they sack the cities of Zamora and León.
- Summer – Roman of Bulgaria dies in captivity in Constantinople. He is succeeded by his brother Samuel (a member of the Cometopuli Dynasty) who takes the Bulgarian title of tsar. He possibly receives his 'imperial crown' from Gregory V (approximate date).
- King Stephen Držislav of Croatia dies after a 28-year reign. His three sons, Svetoslav, Krešimir III and Gojslav, open a violent contest for the throne, weakening the kingdom and allowing Samuel to encroach on the Croatian possessions along the Adriatic.
- Winter – Emperor Otto III travels to Italy, leaving the government of the Holy Roman Empire in the hands of his aunt, Matilda of Quedlinburg. He is accompanied by Bishop Gilbert of Aurillac, his teacher and advisor.
- Trondheim is founded by King Olav Tryggvason. This will function as the main city and capital of Norway, until Bergen is founded in 1070.
- King Constantine III dies after a 2-year reign. Possibly murdered by a dynastic conflict between two rival lines of royalty. He is succeeded by Kenneth III as sole ruler of Alba (Scotland).
- Sabuktigin, founder of the Ghaznavid Dynasty, dies after a 20-year reign. He is succeeded by his son Ismail as emir of Ghazna. But many in the court favor his elder brother Mahmud.
- May 8 – Emperor Tai Zong (Zhao Jiong) dies at Kaifeng after 21-year reign. He is succeeded by his son Zhen Zong as the third ruler of the Song Dynasty.
- Spring – Pope Gregory V is exiled during a rebellion led by Crescentius II (the younger), patrician (the de facto ruler) of Rome. The Crescentii family appoints Giovanni Filagato (former tutor of Otto III) as an antipope under the name John XVI (or XVII), until 998.
- April 23 – Adalbert, exiled bishop of Prague, organises a mission to convert the Old Prussians in north-east Poland. On his way, Adalbert is murdered by pagans on the Baltic coast. His body is bought back for its weight in gold by Duke Bolesław I (the Brave).
- The first documented reference of Gdańsk is made by Adalbert. During his mission he baptises the inhabitants of the city called Gyddannyzc.
- Spring – Otto III retakes Rome and restores power in the papal city. Crescentius II (the Younger) and his followers barricade themselves in Castel Sant'Angelo. Otto's former tutor John Philagathos (Antipope John XVI), who tries to escape into Campania, is pursued by German troops and captured. He is horribly mutilated – his ears, nose and tongue cut off and his eyes are gouged out. Crescentius surrenders at his stronghold and is beheaded. Otto reinstates his cousin, Gregory V, as pope of the Catholic Church.
- Croatian–Bulgarian War: Emperor Samuel launches a military campaign against the Kingdom of Croatia to prevent an alliance between the Serbian principality and the Byzantines. He seizes Dyrrachium (modern-day Durrës in Albania) and advances along the Dalmatian coast. The Bulgarian army is forced to withdraw into Croatian hinterlands (now part of Bosnia and Herzegovina), after the Siege of Zadar.
- Fall – Otto III makes Rome the administrative capital of the Holy Roman Empire and begins the construction of his imperial palace on the Palatine Hill. He restores the ancient Roman Senate to its position of prominence and adopts the title of "Emperor of the Romans". To this Otto adds the apostolic devotion formula servus Jesu Christi ('Servant of Jesus Christ').
- Winter – King Robert II (the Pious) is excommunicated by Gregory V. For reasons of consanguinity, his second marriage to Bertha of Burgundy is not accepted by the Catholic Church.
- Battle of Ghazni: The Afghan prince Mahmud defeats his younger brother Ismail (the ruling emir of the Ghaznavid Dynasty) in battle. He places Ismail for the rest of his life in comfortable captivity – and expands the realm of his late father, Sebuktigin, into the Punjab in northwestern India.
- Summer – Revolt of Tyre: The city of Tyre (modern Lebanon) is stormed by forces of the Fatimid Caliphate. A Byzantine squadron attempts to reinforce but is repulsed by the Fatimid navy. The defenders are massacred or taken captive to Egypt. The Byzantine captives are executed.
- July 19 – Battle of Apamea: Byzantine forces under governor (doux) Damian Dalassenos besiege the fortress city of Apamea for control over northern Syria. The Fatimids send a relief army from Damascus – and defeat the Byzantines, Dalassenos in killed by a Kurdish officer in battle.
- Byōdō-in Temple (located in Yamashiro Province) is built during the Heian Period on orders of Fujiwara no Michinaga, who uses the Buddhist temple as a countryside retreat villa (modern-day Kyoto Prefecture).
- Winter – Otto III makes a pilgrimage through middle Italy from Gargano to Benevento. Stopping by Monte Cassino, where he meets the hermit monk Romuald.
- Bishop Wulfsige III establishes a Benedictine abbey at Sherborne (Dorsetshire).
By place and nameEdit
- King Bermudo II abdicates in favor of his 5-year-old son Alfonso V as ruler of León. Moorish invaders have forced Bermudo to recognize the suzerainty of their leader, Umayyad vizier and the de facto ruler Al-Mansur.
- 9 September (999 or 1000): A Norwegian fleet, commanded by Olaf Tryggvason is defeated by the combined fleet of the Danish king Sweyn Forkbeard and his Swedish counterpart Olaf the Swede during the Battle of Svolder, resulting in Tryggvason's death and the splitting up of Norway between Sweden and Denmark.
- December 30 - Battle of Glenmama: The combined forces of Munster and Meath under Brian Boru (High King of Ireland) inflict a crushing defeat on the allied armies of Leinster and Dublin near Lyons Hill (County Kildare).
- The Karakhanids invade from north of the Syr Darya River which ends the Samanid Empire (modern Iran). The Samanid domains are split up between the Ghaznavid Dynasty and the Karakhanids.
- February 18 – Pope Gregory V dies after a 3-year pontificate in which he has been forced to flee Rome by the Crescentii family. He is succeeded by Sylvester II as the 139th pope of the Catholic Church.
- Bishop Aldhun consecrates a cathedral (later Durham Cathedral) at the location where the remains of St. Cuthbert are relocated. The remains from Lindisfarne are moved of the danger of Viking raids.
- Sigmundur Brestisson, a Viking chieftain, introduces Christianity in the Faroe Islands.
- John Haywood (1995). The Historical Atlas of the Vikings: Raids on Æthelred's Kingdom, pp. 118–119. ISBN 978-0-140-51328-8.
- John Haywood (1995). The historical Atlas of the Vikings: Raids on Æthelred's Kingdom, p. 118. ISBN 978-0-140-51328-8.
- J. Norwich (1991). Byzantium: The Apogee, p. 257. ISBN 0-394-53779-3.
- Bernard S. Bachrach, Warfare and Military Organization in Pre-Crusade Europe (Ashgate Publishing, Aldershot, UK and Burlington, Vermont, 2002), IX, p. 66.
- Reuter, Timothy (1992). Germany in the Early Middle Ages, 800-1036, London and New York.
- Reuter, Timothy (1999). The New Cambridge Medieval History, Volume III, p. 257. ISBN 978-0-521-36447-8.
- John Haywood (1995). The Historical Atlas of the Vikings: Raids on Æthelred's Kingdom, p. 119. ISBN 978-0-140-51328-8.
- Read, Piers Paul (1999). The Templars. Weidenfeld & Nicolson, Orion Publishing Group. ISBN 0-297-84267-6.
- "Boleslaus II the Pious". www.kralovskacesta.cz. Retrieved 15 September 2012.
- Twitchett, Denis; Tietze, Klaus-Peter (1994). The Cambridge History of China, Volume 6, pp. 43–153. ISBN 0-521-24331-9.
- François Neveux, A Brief History of the Normans (Constable and Robinson, 2008) p. 74.
- Gil, Moshe (1997). A History of Palestine, 634–1099, pp. 369–370. Cambridge: Cambridge University Press. ISBN 0-521-59984-9.
- Paul Stephenson (2003). The Legend of Basil the Bulgar-Slayer, Cambridge University Press. ISBN 0-521-81530-4.
- Collins, Roger (1983). Early Medieval Spain, p. 199. New York: St. Martin's Press. ISBN 0-312-22464-8.
- Christine Schefte (20 June 2012). "Hva husker du fra 1000-årsjubileet?" (in Norwegian). Adressa. Retrieved 5 March 2016.
- Richard Brzezinski (1990). History of Poland: The Piast Dynasty - Bolesław the Brave, p.16. ISBN 83-7212-019-6.
- John Norwich (1991). Byzantium: The Apogee, pp. 255–256. ISBN 0-394-53779-3.
- John Norwich (1991). Byzantium: The Apogee, p. 257. ISBN 0-394-53779-3.
- Reuter, Timothy (1992). The New Cambridge Medieval History, Volume III, p. 258. ISBN 978-0-521-36447-8.
- James Palmer (2014). The Apocalypse in the Early Middle Ages, p. 215. Cambridge University Press.
- Gil, Moshe (1997). A History of Palestine, 634–1099, pp. 369–370. Cambridge University Press. ISBN 0-521-59984-9.
- Uji Travel: Byodoin Temple - Japan Guide (Retrieved August 4, 2017).