1154 CE
A year that saw the end of the Anarchy in England with the accession of Henry II as king, the death of Roger II of Sicily, and the passing of the influential mapmaker al-Idrisi's great geographical work.
Geopolitics & Diplomacy
- Henry II was crowned King of England on December 19 at Westminster Abbey, ending the nineteen years of civil war known as the Anarchy and founding the Plantagenet dynasty.
- Henry II's accession followed the Treaty of Wallingford in 1153, in which the dying King Stephen agreed that Henry would succeed him rather than Stephen's own surviving son.
- Henry II inherited an empire stretching from the Scottish border through England and across western France, including Normandy, Anjou, Maine, Touraine, and Aquitaine.
- King Roger II of Sicily died in February, succeeded by his son William I, who would struggle to maintain his father's legacy of effective governance over the diverse kingdom.
Science & Discovery
- The Arab geographer Muhammad al-Idrisi completed his great work of geography, the Tabula Rogeriana, at the court of Roger II of Sicily, producing one of the most advanced world maps of the medieval period.
Climate & Environment
- Atmospheric carbon dioxide concentration was approximately 275 parts per million, as later confirmed by ice core analysis.
Culture & Society
- Nicholas Breakspear was elected Pope Adrian IV, becoming the only Englishman ever to hold the papacy.
- The estimated world population was approximately 343 million.