1159
Al-Idrisi's Tabula Rogeriana completed
The Moroccan geographer Muhammad al-Idrisi presented his finished world atlas to King William I of Sicily - seventy meticulously drawn maps and a comprehensive geographical text describing the known world from the frozen seas of Scandinavia to the gold-rich kingdoms south of the Sahara, from Korea to Britain. The Tabula Rogeriana remained the most accurate and detailed depiction of the world for the next three centuries.
John of Salisbury publishes Policraticus
The English humanist and Becket ally finished his Latin treatise on statecraft, the Policraticus. It is the first medieval European work to argue systematically that tyrants may be removed, even killed, by their subjects - a seed for much later political theory. John drew on classical Roman sources as well as contemporary observation, producing a work that reads as part philosophical treatise, part satirical portrait of the corrupt courts he had observed.
Kilij Arslan II reunifies the Sultanate of Rum
The young Seljuk sultan of Rum defeated his brother and various Danishmendid rivals to reconsolidate Turkish power across the Anatolian plateau, establishing the city of Konya as a prosperous and cultured capital. Under his long and stable reign, the sultanate would become a powerful magnet for Persian poets, wandering Sufi mystics, and displaced scholars - presaging the brilliant court culture that would flourish there before the Mongol storm.
Double papal election
Cardinals in Rome split bitterly between Alexander III and the imperial-backed Victor IV. Barbarossa convened a council at Pavia that ruled for Victor. The resulting schism lasted eighteen years and would drag Germany, Sicily, England, and France into an unwanted theological diplomatic mess. Every Christian kingdom was forced to choose sides, and the alignment of powers around the two claimants shaped European diplomacy for a generation.
Adrian IV's letter to Barbarossa
Pope Adrian IV wrote a letter to Frederick Barbarossa using the Latin word beneficium, which could mean either favor or fief. The emperor's court took offense at the suggestion that the empire was a papal fief. The careless choice of word hastened the rupture that became the schism of 1159.