# 1090

Year 1090 (MXC) was a common year starting on Tuesday of the Julian calendar.

## Events
### By place
#### Europe

* A third Almoravid expedition is launched in Al-Andalus, designed to finally subdue the Taifa's Kingdoms. The cities of Córdoba, Seville, Granada, Málaga, Almería and Ronda fall to the troops of Sultan Yusuf ibn Tashfin.
* King Stephen II of Croatia becomes involved in an open conflict between factions of the Croatian nobility, who reassert their traditional rights in their own counties.

#### Seljuk Empire

* Hassan-i Sabbah founds the Nizari Ismaili state after taking control of the Alamut Castle and organising the military group called the Order of Assassins.

#### Africa

* Béjaïa (or Bugia) becomes the capital of the Hammadid dynasty in modern-day Algeria. It becomes an important port and centre of culture.

### By topic
#### Arts and Culture

* Troubadours begin playing in western Aquitaine (Poitou and Saintonge) and Gascony (approximate date).

#### Science and Technology

* Qin Guan, Chinese poet of the Song dynasty, writes the Can Shu (Book of Sericulture), which describes a silk-reeling machine that has the world's oldest known mechanical belt drive.

## Births

* January 17 – Qin Hui, Chinese chancellor (d. 1155)
* unknown dates
** Frederick II ("the One-Eyed"), German nobleman (d. 1147)
** Dōin (Fujiwara no Atsuyori), Japanese waka poet (d. 1179)
* probable
** Adolf III, German count of Berg and Hövel (d. 1152)
** Agnes I, German abbess of Quedlinburg (approximate date)
** Alaungsithu, Burmese king of the Pagan dynasty (d. 1167)
** Arnold of Brescia, Italian canon regular (approximate date)
** Bernard of Clairvaux, French abbot and theologian (d. 1153)
** Chen Yuyi, Chinese politician of the Song dynasty (d. 1138)
** Eliezer ben Nathan, German rabbi and liturgical poet (d. 1170)
** Eric II ("the Memorable"), king of Denmark (approximate date)
** Fujiwara no Akisuke, Japanese nobleman and poet (d. 1155)
** Juliane de Fontevrault, illegitimate daughter of King Henry I of England
** Conrad I, Duke of Zähringen, German nobleman and rector of Burgundy (d. 1152)
** Niklot (or Nyklot), Obotrite prince and tribal chief (d. 1160)
** Robert, 1st Earl of Gloucester, illegitimate son of King Henry I of England
** Theobald II, Count of Champagne ("the Great"), French nobleman
** Theobald of Bec, Norman churchman, archbishop of Canterbury
** William de Mohun, 1st Earl of Somerset, Anglo-Norman nobleman

## Deaths

* March 22 – García II, king of Galicia and Portugal (b. 1042)
* April 16 – Sikelgaita, Lombard duchess of Apulia (b. 1040)
* May 3 – Adelaide of Rheinfelden, queen consort of Hungary
* May 12 – Liutold of Eppenstein, German nobleman
* May 18 – Berthold of Rheinfelden, German nobleman
* June 26 – Jaromír, Bohemian prince and bishop
* July 3 – Egbert II (or Ekbert), German nobleman
* August 11 – Fujiwara no Atsuie, Japanese nobleman (b. 1033)
* August 13 – Constance of Normandy, duchess of Brittany
* unknown dates
** Abd al-Jalil ibn Wahbun, Moorish poet and writer
** Fayun Faxiu, Chinese Chan Buddhist monk (b. 1027)
** Richard fitz Gilbert, Norman nobleman (b. c.10350
** Guo Xi, Chinese landscape painter
** St Isaiah of Rostov, Kievan missionary and bishop
** Raynald I, French Benedictine abbot (b. 1059)
** William of Poitiers, French priest and chronicler (b. c.1020)
* probable
** Osbern of Canterbury, English hagiographer