September 29. September 29 is the 272nd day of the year (273rd in leap years) in the Gregorian calendar; 93 days remain until the end of the year. Events Pre-1600 61 BC ??? Pompey the Great celebrates his third triumph for victories over the pirates and the end of the Mithridatic Wars on his 45th birthday. 1011 ??? Danes capture Canterbury after a siege, taking ??lfheah, archbishop of Canterbury, as a prisoner. 1227 ??? Frederick II, Holy Roman Emperor, is excommunicated by Pope Gregory IX for his failure to participate in the Crusades during the Investiture Controversy. 1267 ??? The Treaty of Montgomery recognises Llywelyn ap Gruffudd as Prince of Wales, but only as a vassal of King Henry III. 1364 ??? During the Hundred Years' War, Anglo-Breton forces defeat the Franco-Breton army in Brittany, ending the War of the Breton Succession. 1567 ??? During the French War...