The 740 Constantinople earthquake took place on 26 October, 740, in the vicinity of Constantinople and the Sea of Marmara.[1]
History
In Constantinople, the earthquake caused the collapse of many public buildings. The Walls of Constantinople were also damaged. The casualties in Constantinople reportedly included over 1,000 people.[1]
The earthquake reportedly destroyed a number of towns in Thrace. It also damaged the cities of Nicaea (İznik), Nicomedia (İzmit), and Praenetus.[1]
The historians Theophanes the Confessor (8th-9th centuries) and George Kedrenos (11th century) reported that the earthquake caused the sea to retreat from the coast in many places. The sea soon returned, and flooded many towns.[1] The description given matches that of a seismic sea-wave (tsunami).[1]
The date of the earthquake is recorded by (among others) Anastasius Bibliothecarius (9th century), Joannes Zonaras (12th century), Carolus Sigonius (16th century), Caesar Baronius (16th-17th centuries), and Sethus Calvisius (16th-17th centuries).[1]