|1089 by topic|
|Birth and death categories|
|Births – Deaths|
|Establishments and disestablishments categories|
|Establishments – Disestablishments|
|Ab urbe condita||1842|
|Balinese saka calendar||1010–1011|
|English Regnal year||2 Will. 2 – 3 Will. 2|
|Chinese calendar||戊辰年 (Earth Dragon)|
3785 or 3725
— to —
己巳年 (Earth Snake)
3786 or 3726
|- Vikram Samvat||1145–1146|
|- Shaka Samvat||1010–1011|
|- Kali Yuga||4189–4190|
|Japanese calendar||Kanji 3|
|Minguo calendar||823 before ROC|
|Seleucid era||1400/1401 AG|
|Thai solar calendar||1631–1632|
1215 or 834 or 62
— to —
1216 or 835 or 63
Year 1089 (MLXXXIX) was a common year starting on Monday (link will display the full calendar) of the Julian calendar.
- King Demetrius Zvonimir of Croatia dies after a 12-year reign, and is succeeded by Stephen II. Zvonimir's widow, Queen Helena, plots the inheritance of the Croatian crown for her brother, King Ladislaus I of Hungary.
- June 24 – Viscount Gaston IV of Béarn (supported by French crusaders) reconquers the Aragonese city of Monzón, from Emir Al-Mustain II of the Taifa of Zaragoza.
- August 18 – Emperor Henry IV marries Eupraxia (daughter of Grand Prince Vsevolod I) at Cologne. She is crowned and assumes the name Adelaide (or Adelheid).
- King George II abdicates the throne in favour of his 16-year-old son David IV (the Builder) who becomes ruler of Georgia (until 1125).
- Northumbria is divided by King William II into the counties of Northumberland, County Palatine of Durham, Yorkshire, Westmorland and Lancashire.
- August 11 – A powerful earthquake is recorded in England.
- March 21 – Cîteaux Abbey, the first Cistercian monastery, is established by a group of French monks under Robert of Molesme in southern France.
- September – The Synod of Melfi, led by Pope Urban II (his first papal council), issues decrees against simony and clerical marriage.
- September – A church council, held in Constantinople, discuses relations between Eastern and Western Christianity.
- Abraham ibn Ezra, Jewish rabbi and philosopher (d. 1167)
- Berthold of Zwiefalten, German abbot and writer (d. 1169)
- Dahui Zonggao, Chinese Zen Buddhist monk (d. 1163)
- Han Shizhong, Chinese general (Song Dynasty) (d. 1151)
- Mahsati, Persian female poet and writer (approximate date)
- Richard de Luci, Norman High Sheriff of Essex (d. 1179)
- Sigurd I (the Crusader), king of Norway (d. 1130)
- Wulgrin II, count of Angoulême (approximate date)
- May 24 – Lanfranc, archbishop of Canterbury
- May 29/30 – Mah-i Mulk Khatun wife of caliph al-Muqtadi (r. 1075–1094).
- May 31 – Sigwin of Are, archbishop of Cologne
- October 6 – Adalbero, bishop of Würzburg
- November 11 – Peter Igneus, Italian cardinal-bishop
- December 22 – William the Walloon, French abbot
- Agnes of Aquitaine, Italian countess of Savoy
- Demetrius Zvonimir, king of Croatia and Dalmatia
- Donnchad mac Domnaill Remair, king of Dublin
- Durandus of Troarn, French monk and theologian
- Isaac ibn Ghiyyat, Jewish rabbi and philosopher
- Mieszko Bolesławowic, Polish prince of Kraków
- Renauld II, French count of Nevers and Auxerre
- Theobold III (or Thibaut), French nobleman
- ^ Canellas, Angel (1951). "Las Cruzadas de Aragon en el Siglo XI". Argensola: Revista de Ciencias Sociales del Instituto de Estudios Altoaragoneses. 7. ISSN 0518-4088. Archived from the original on July 14, 2014. Retrieved February 22, 2012.
- ^ Pope Bl. Urban II, Catholic Encyclopedia, http://www.newadvent.org/cathen/15210a.htm
- ^ Siecienski, Anthony Edward (2010). The Filioque: History of a Doctrinal Controversy. Oxford University Press. p. 117. ISBN 978-0-19-537204-5.