Year 756 (DCCLVI) was a leap year starting on Thursday (link will display the full calendar) of the Julian calendar. The denomination 756 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Byzantine Empire Byzantine–Bulgarian War: Emperor Constantine V builds a series of fortifications along the Byzantine frontier on the Danube, and starts settling Christian Armenians and Syrians in the Thracesian Theme. In response, Kormisosh, ruler (khagan) of the Bulgarian Empire, demands the payment of tribute. Constantine refuses, and the Bulgars raid into Thrace, reaching the Anastasian Wall stretching between the Black Sea and the Sea of Marmara (near the outskirts of Constantinople). Battle of Marcellae: Constantine V sends a Byzantine expeditionary force (500 ships and 6,000 cavalry) to Thrace, and defeats the Bulgars around the Danube Delta and near the fortress city of Markeli (modern Bulgaria). Kormisosh is forced to accept a peace treaty, and confirms the existing frontier. Due to the constant political crisis, the Bulgarian Empire is on the verge of destruction. Kormisosh is deposed during a palace coup and succeeded by Vinekh, a member of the Vokil clan. Europe King Aistulf of the Lombards again threatens Rome with a view to making it his capital, but the Franks under Pepin III ("the Short") arrives with his sons Charles and Carloman, defeats Aistulf, and confers the Donation of Pepin, which establishes the Papal States (including the lands of Ravenna and the Pentapolis). Pepin has taken territory that legally belongs to the Byzantine Empire; he gives it to Pope Stephen II. Aistulf dies in a hunting accident, and is succeeded by Desiderius as king of the Lombards. Ex-king Ratchis attempts unsuccessfully to seize the throne, but is opposed by Stephen II. Galla Gaulo is deposed, blinded and exiled. He is succeeded by Domenico Monegario as the sixth doge of Venice. During his reign Venetian maritime traders become increasingly active. May – Prince Abd al-Rahman I and his followers capture the city of Seville without violence. He defeats Yusuf ibn 'Abd al-Rahman al-Fihri in a battle for control of the Muslim-ruled parts of the Iberian Peninsula (al-Andalus). Abd al-Rahman establishes the Emirate of Córdoba. During his reign trade and culture flourish, along with the construction of Islamic architecture (including the Great Mosque of Córdoba). Britain Battle of Newanbirig: Kings