1170
Murder of Thomas Becket
Four of Henry II's knights, spurred by their king's angry musings at his Christmas court, rode for Canterbury, cornered the archbishop in his own cathedral at vespers, and hacked open his skull on the stone flags. The wayward monks gathered his blood in bowls. Within three years he was canonized.
Syria earthquake
A massive earthquake rattled the Levant from Aleppo to Damascus, toppling Crusader castles and Muslim citadels alike. The tremor was followed by months of aftershocks. Contemporary chroniclers on both sides saw it as a divine rebuke for the ongoing wars. The quake destroyed sections of the Krak des Chevaliers and forced both Nur al-Din and the Crusader lords into a rare informal truce while they rebuilt their shattered fortifications.
Anglo-Normans take Dublin
Strongbow's forces stormed the wooden city walls and chased its Norse king Hasculf out to sea. Within a year Henry II himself would land in Ireland to place himself between his over-powerful vassal and the native kingdoms, beginning the formal English lordship of Ireland. Henry received the submission of most Irish kings at a parliament in Waterford, establishing a pattern of nominal Irish acknowledgment and practical Irish resistance that would persist for centuries.
Lubeck refounded
Henry the Lion, duke of Saxony, refounded the city of Lubeck at the head of the Trave estuary after a fire. The rebuilt town, laid out on a grid with a stone cathedral and market, would quickly become the queen of the Baltic trade and the cradle of the Hanseatic League.
Coronation of the Young King
Henry II had his fifteen-year-old son crowned king of England during his own lifetime - partly to ensure the succession, partly to provoke Becket, who as Archbishop of Canterbury alone had the right to crown. The Archbishop of York officiated instead. Becket excommunicated him. The coronation created the anomaly of two living kings of England and poisoned relations between father and son for the remaining thirteen years of the young king's life.