August 15

636 – Arab–Byzantine wars: The Battle of Yarmouk between the Byzantine Empire and the Rashidun Caliphate begins. 717 – Arab–Byzantine wars: Maslama ibn Abd al-Malik begins the Second Arab Siege of Constantinople, which will last for nearly a year. 718 – Arab–Byzantine wars: Raising of the Second Arab Siege of Constantinople. 747 – Carloman, mayor of the palace of Austrasia, renounces his position as majordomo and retires to a monastery near Rome. His brother, Pepin the Short, becomes the sole ruler (de facto) of the Frankish Kingdom. 778 – The Battle of Roncevaux Pass takes place between the army of Charlemagne and a Basque army. 805 – Noble Erchana of Dahauua grants the Bavarian town of Dachau to the Diocese of Freising 927 – The Saracens conquer and destroy Taranto. 982 – Holy Roman Emperor Otto II is defeated by the Saracens in the Battle of Capo Colonna, in Calabria. 1018 – Byzantine general Eustathios Daphnomeles blinds and captures Ibatzes of Bulgaria by a ruse, thereby ending Bulgarian resistance against Emperor Basil II's conquest of Bulgaria. 1038 – King Stephen I, the first king of Hungary, dies; his nephew, Peter Orseolo, succeeds him. 1057 – King Macbeth is killed at the Battle of Lumphanan by the forces of Máel Coluim mac Donnchada. 1070 – The Pavian-born Benedictine Lanfranc is appointed as the new Archbishop of Canterbury in England. 1096 – Starting date of the First Crusade as set by Pope Urban II. 1185 – The cave city of Vardzia is consecrated by Queen Tamar of Georgia. 1224 – The Livonian Brothers of the Sword, a Catholic military order, occupy Tarbatu (today Tartu) as part of the Livonian Crusade. 1237 – Spanish Reconquista: The Battle of the Puig between the Moorish forces of Taifa of Valencia against the Kingdom of Aragon culminates in an Aragonese victory. 1248 – The foundation stone of Cologne Cathedral, built to house the relics of the Three Wise Men, is laid. (Construction is eventually completed in 1880.) 1261 – Michael VIII Palaiologos is crowned as the first Byzantine emperor in fifty-seven years.