|Ab urbe condita||1801|
|Balinese saka calendar||969–970|
|English Regnal year||N/A|
|Chinese calendar||丁亥年 (Fire Pig)|
3744 or 3684
— to —
戊子年 (Earth Rat)
3745 or 3685
|- Vikram Samvat||1104–1105|
|- Shaka Samvat||969–970|
|- Kali Yuga||4148–4149|
|Japanese calendar||Eishō 3|
|Minguo calendar||864 before ROC|
|Seleucid era||1359/1360 AG|
|Thai solar calendar||1590–1591|
1174 or 793 or 21
— to —
1175 or 794 or 22
|Wikimedia Commons has media related to 1048.|
- September 18 – Battle of Kapetron: A combined Byzantine-Georgian army under the Byzantine generals Aaronios and Katakalon Kekaumenos (supported by the Georgian duke Liparit IV) confronts the invading Seljuk Turks led by Ibrahim Inal (a half-brother of Sultan Tughril) at Kapetron (near modern-day Pasinler). The Byzantines defeat their opposing Turkish forces in the flanks, but in the centre Ibrahim Inal captures Liparit and is able to safely withdraw the Byzantine territory, laden with spoils and captives, including Liparit. 
- Winter – Emperor Constantine IX sends an embassy with gifts and a ransom for the release of Liparit IV to Tughril. However, the sultan magnanimously sets free Liparit on condition that he will never again fight the Seljuks.
- Winter – Emperor Henry III (the Black) appoints his cousin, Bishop Bruno of Toul (from the family of the counts of Egisheim-Dagsburg in Upper Alsace), as successor of Damasus II at a assembly at Worms.
- The city of Oslo is founded by King Harald III (Hardrada) of Norway (approximate date).
- 1048 or 1066 - End of the Viking Age: Vikings make an unsuccessful raid on the Kingdom of England; The raiders flee to Flanders (modern Belgium).
- King Edward the Confessor goes to war against Flanders, blockading the English Channel with a fleet based at Sandwich in Kent.
- May 18 – Omar Khayyam, Persian mathematician and poet (d. 1131)
- May 25 – Shen Zong, emperor of the Song Dynasty (d. 1085)
- Alexios I (Komnenos), Byzantine emperor (d. 1118)
- Arwa al-Sulayhi, queen and co-ruler of Yemen (d. 1138)
- Harding of Bristol, English sheriff reeve (approximate date)
- Magnus II (Haraldsson), king of Norway (approximate date)
- Matilda of Germany, duchess of Swabia (d. 1060)
- Peter I, Italian nobleman (House of Savoy) (d. 1078)
- Sheikh Ahmad-e Jami, Persian Sufi writer and poet (d. 1141)
- Turgot of Durham, Scottish bishop (approximate date)
- January 25 – Poppo, abbot of Stavelot-Malmedy (b. 977)
- June 1 – Minamoto no Yorinobu, Japanese samurai (b. 968)
- June 7 – Berno of Reichenau, German abbot
- August 9 – Damasus II, pope of the Catholic Church
- November 11 – Adalbert, duke of Upper Lorraine (b. 1000)
- December 9 – Al-Biruni, Persian scholar and polymath (b. 973)
- Æthelstan of Abingdon, English abbot (or 1047)
- Cenn Fáelad Ua Cúill, Irish poet and Chief Ollam
- Humbert I, founder of the House of Savoy (or 1047)
- Jing Zong, Chinese empress of Western Xia (b. 1003)
- Mael Fabhaill Ua hEidhin, king of Hy Fiachrach
- Rainulf II (Trincanocte), Italo-Norman nobleman
- Beihammer, Alexander Daniel (2017). Byzantium and the Emergence of Muslim-Turkish Anatolia, ca. 1040–1130. Taylor & Francis. pp. 77–79. ISBN 978-1-351-98386-0.
- "Inside Oslo: Inside". Trip Advisor. Retrieved March 25, 2010.
- Palmer, Alan; Veronica (1992). The Chronology of British History. London: Century Ltd. pp. 50–51. ISBN 0-7126-5616-2.