Walls of Constantinople - Sea Walls

Sea Walls

The seaward walls (Greek: τείχη παράλια, teichē paralia) enclosed the city on the sides of the Sea of Marmara (Propontis) and the gulf of the Golden Horn (χρυσοῦν κέρας). Although the original city of Byzantium certainly had sea walls, traces of which survive, the exact date for the construction of the medieval walls is a matter of debate. Traditionally, the seaward walls have been attributed by scholars to Constantine I, along with the construction of the main land wall. However, the first actual reference to their construction comes in 439, when the urban prefect Cyrus of Panopolis (in sources often confused with the praetorian prefect Constantine) was ordered to repair the city walls and complete them on the seaward side. This activity is certainly not unconnected to the fact that in the same year, Carthage fell to the Vandals, an event which signaled the emergence of a naval threat in the Mediterranean. This two-phase construction remains the general consensus; Cyril Mango however doubts the existence of any seaward fortifications during Late Antiquity, as they are not specifically mentioned as extant by contemporary sources until much later, around the year 700.

The Sea Walls were architecturally similar to the Theodosian Walls, but of simpler construction. They were formed by a single wall, considerably lower than the land walls, with inner circuits in the locations of the harbours. Enemy access to the walls facing the Golden Horn was prevented by the presence of a heavy chain or boom, installed by Emperor Leo III (r. 717–741), supported by floating barrels and stretching across the mouth of the inlet. One end of this chain was fastened to the Tower of Eugenius, in the modern suburb of Sirkeci, and the other in Galata, to a large, square tower, the Kastellion, the basement of which was later turned into the Yeraltı (underground) Mosque. At the same time, on the Marmara coast, the city's defence was helped by strong currents, which made an attack by a fleet almost impossible. According to Geoffrey of Villehardouin, it was for this reason that the Fourth Crusade did not attack the city from this side.

During the early centuries of its existence, Constantinople faced few naval threats. Especially after the wars of Justinian, the Mediterranean had again become a "Roman lake". It was during the first siege of the city by the Avars and the Sassanid Persians that for the first time, a naval engagement was fought off the city itself. However, after the Arab conquests of Syria and Egypt, a new naval threat emerged. In response, the sea walls were renovated in the early 8th century under Tiberios III (r. 698–705) or Anastasios II (r. 713–715). Michael II (r. 820–829) initiated a wide-scale reconstruction, eventually completed by his successor Theophilos (r. 829–842), which increased their height. As these repairs coincided with the capture of Crete by the Saracens, no expense was spared: As Constantine Manasses wrote, "the gold coins of the realm were spent as freely as worthless pebbles". Theophilos' extensive work, essentially rebuilding the sea walls, is testified to by the numerous inscriptions found or otherwise recorded that bear his name, more than those of any other emperor. Despite future changes and restorations, these walls would essentially protect the city until the end of the empire.

During the siege of the city by the Fourth Crusade, the sea walls nonetheless proved to be a weak point in the city's defences, as the Venetians managed to storm them. Following this experience, Michael VIII Palaiologos (r. 1259–1282) took particular care to heighten and strengthen the seaward walls immediately after the Byzantine recapture of the city in 1261, since a Latin attempt to recover the city was regarded as imminent. Furthermore, the installation of the Genoese at Galata across the Golden Horn, agreed upon in the Treaty of Nymphaeum, posed a further potential threat to the city. Time being short, as a Latin attempt to recover the city was expected, the sea walls were heightened by the addition of two-meter high wooden and hide-covered screens. Ten years later, facing the threat of an invasion by Charles d'Anjou, a second line of walls was built behind the original maritime walls, although no trace of them survives today.

The walls were again restored under Andronikos II Palaiologos (r. 1282–1328) and again under his successor Andronikos III Palaiologos (r. 1328–1341), when, on 12 February 1332, a major storm caused breaches in the wall and forced the seaward gates open. In 1351, when the empire was at war with the Genoese, John VI Kantakouzenos again repaired the walls, and even opened a moat in front of the wall facing the Golden Horn. Other repairs are recorded for 1434, again against the Genoese, and again in the years leading up to the final siege and fall of the city to the Ottomans, partly with funds provided by the Despot of Serbia, George Brankovic.