Since the foundation of the Eastern State (328 A.D.) until 1346 A.D. when the island was conquered by the Genovese, Chios was Byzantine. There are no secure historical resources for the period from 300 A.D. to 900 A.D.. It has been considered as a period of no recorded history . The first emperor of Byzantium, Constantine the Great, deprived Chios of every work of art; he took what the Romans had not taken. All those works of art were transferred to Constantinople, the new capital city of the state. The new capital city was decorated by the most beautiful works of art (what had been left by the Romans, the Goths and by the pirates)which had been removed by ancient temples and other buildings of Chios. Later, in the reign of Theodosius the Young (403-450 A.D.) the rest of the works of art were removed. It was then that the famous four gold-plating horses were removed too. They were taken to Constantinople and placed above the railing of the hippodrome.

The gold horses of Chios, a Chian artist’s work around 200 B.C. decorated Nero’s and Traianos’ arches in Rome. Later, they were transferred to Paris by Napoleon and decorated the Palace of Ceramic. When Napoleon was not an emperor anymore, they were moved to Venice. Nowadays they can be found on the top of the Cathedral of Saint Marcos in Venice.

In the reign of Emperor Ioustiniani, Chios was a prey to pirates. The Arab and Saracens pirates looted the coastline of the Minor Asia and Chios. It is also mentioned that General Velissarios was sent from Constantinople to fight the pirates. But because of the rough sea, he disembarked in Volissos. There he built the castle of Volissos and he named the village after him.

Around 625 A.D., the Syrian pirate Moavia, the leader of the pirates, looted Chios. In the reign of Consta II (also known as Pogonatos), Chios was once again ruined by the Arab pirates (657 A.D.) The temple of the patron saint of Chios was completely destroyed.

During the years that followed until 900 A.D., Chios, as well as the other islands nearby, were attacked by the pirates. Many Chians were forced to leave the island and to inhabit in the mainland, like the Minor Asia, to save themselves. Around 900 A.D. the Castle of Chios was built. It was built as a coastal fortress to protect the city from the pirates. Starting from that period, the life on the island began to normalize and its naval force and trade to become stronger.

In 1027 A.D., in the reign of Constantine VIII, the general of Chios (Prefect of the island) was Verivois. It was then that the Turks attacked the island and destroyed it completely. General Verivois asked for help from the general of the island Samos, Georgios Theodorakos. He agreed to help him and they managed to defeat the Turkish pirates and to capture twelve ships with their crew.

During the last years of the eleventh century, the history of the middle century of Chios begins. In that period the emperor of Byzantium, Alexios Comninos, had to fight against the Scythes and the Patsinakis. So the Turk partisan, Tzahas, had the chance to gather forty ships and to have experienced warriors as a crew. He attacked and he conquered Focea, Kalsomines, Lesvos and Chios (1093 A.D.). As soon as Emperor Alexios heard of it, he sent a big enough fleet under the command of General Nikitas Kastamonitis. In the battle against Tzahas’ army, the General was defeated and he lost many ships.

The moment the Emperor was informed about Kastamonitis’ defeat, he sent another fleet under the command of Constantine Dalassinos, who was a fighter. When Dalassinos arrived in Chios, he decided to besiege the Fortress of the city, before going back to Smyrna where Tzahas was. He destroyed the Wall located between two towers and so he terrified the Turks. Dalassinos prevented his soldiers from looting the island. Tthe Turks took advantage of that inaction and they built a new wall. They used hard materials to protect it from the stones being hurled, waiting for Tzahas to help them. He came to help them with an army of eight thousand Turks. When Dalassinos heard about it, he commanded the admiral of his fleet, Opo, to attack Tzahas. Tzahas had placed all his ships in such a way that they formed a huge chain which was impossible for anyone to pass through it or to break it. Admiral Opo got scared of the enemy’s ships and returned to Chios. Tzahas’s army disembarked the Walls. Dalassinos dug a canal and ordered his soldiers to hide in it. Tzahas commanded the Turks to attack the Byzantines. The Latins, who were a great part of the Byzantine army, attacked the Turks but most of them were killed. The ones that managed to save their lives were on the run and boarded on the ships to abandon the island. Seeing the Latins and the Celts’ rout, the Byzantines retreated into the Walls. Without anyone and anything being on his way, Tzahas went on to seize some ships and sent some of his men to Dalassinos to sign a treaty of peace, since he had realized that it would be hard for him to defeat the Byzantines. When the two commanders met the next day, Tzahas said that he was willing to withdraw his army only if Emperor Alexios would grant him the privileges he had in the reign of Emperor Nikiforos. Dalassinos replied that he did not trust him and that he was not in a position to solve his problems without the Emperor’s permission. Meanwhile, Doukas Ioannis was on this way to help the Byzantines. Tzahas decided to sail to Smyrna in order to reassemble his troops. But then, Dalassinos made a quick decision and he defeated the Turks as well as he conquered the castle. He sailed to the island of Lesvos to liberate it from the Turks too having already left some of his army to guard the island of Chios. Tzahas was invited by Sultan Klitz Arslan to a feast during which Tzahas was murdered.

In 1124 A.D., in the reign of Emperor Ioannis Komninos, the admiral of the Venetian fleet, Dominic Micelles, on his way from Tyros, he conquered the Cyclades and Chios; he enslaved men and women and looted the islands. Later he returned to Venice. It was then that St Isidoros relics was stolen, without his head, and was transferred to the temple of St Marcos. Five hundred years later his head was also taken to Venice by an unknown Greek who was rewarded for what he did.

In 1171 A.D. Chios suffered from plague and many inhabitants of the islands died. The Venetians did not have any sailors any more (because most of them died of the plague) to work on their ships so they decided to burn them down so that the Greeks could not have them. They were forced to leave the island and they returned to their homeland only with seventeen ships.

In 1204 A.D., after the fall of Constantinople by the crusaders, the Kingdom of Byzantium was split in half: half of it was ruled by the Franks (French) and the other one by the Venetians. Chios was, then, ruled by the Venetians. In 1235 A.D. the Emperor of Nice, Ioannis Doukas Vatatzis, tried to send the Latins away. His fleet conquered the islands of Chios and Lesvos. But unfortunately, that did not last long. In 1261 A.D. when the Byzantines reestablished their power over Constantinople, Emperor Michael VIIII Palaiologos agreed that the Genovese would establish an official trade station. He also granted them land and farms because he wanted to thank them for their help and support in the war against the crusaders. So the Emperor unified the two third of the conquered countries in his state and he granted one third of it to the several commanders.

Around 1300 A.D. Turkish pirates attacked and looted Chios many times. Pahimeris, the historian, mentions that the barbarians had been looting and burning the island for six months. In 1301-1302 A.D. thirty Turkish people devastated the island. Most of the inhabitants died, apart from very few who barricaded themselves in the castle. Very few Chians, with his wives and children, managed to board on one of the four hundred ships being in the harbour and leave the island. But while they were sailing towards Scyros they shipwrecked and died. The total devastation and destruction of the island happened in 1303 A.D. when Catalan pirates, under the command of Contoniero Rogigo de Flor, arrived in the island. The pirates stayed on the island for the winter, in 1303 A.D. and fought the Turkish pirates. In the grand raid the Turkish pirates did in 1304 A.D., they massacred not only the Chians but also the Catalan guards.

Since the islands were in a terrible situation because of the pirates’ raids, the Genovese commander, Benedetto Zacharias, asked the Emperor to allot him the island of Chios. The Emperor never replied to him and then the commander made the arbitrary decision to invade the island. (1304 A.D.) Emperor Andronikos was then forced to allot Chios to Zacharias for ten years, under the condition that the imperial flag would wave on the island and the Genovese would offer their men to the imperial army. So Zacharias became the master and commander of the island, he sent the pirates away and he rebuilt the ruined houses. He also built a fort and he started trading the mastic. When Zacharias died, he was succeeded by his first born son, Palaiologos who made a fortune by exploiting the island until 1314 A.D. When his son died too, his two brothers Martinos and Benedetto II succeeded him. Besides the island of Chios, they also inherited their father’s cunning. So they kept deceiving the Emperor and every time they managed to be granted ten more years of ruling the island. In 1329 A.D. Benedetto II due to financial disagreement with his brother, he asked for Emperor Andronikos’ help to turn against him. The Emperor agreed and sent him one hundred and five ships in the autumn, in 1329 A.D. Martinos got scared and told the Emperor that he was at his disposal. So he was given the permission to abandon the island with his family. Benedetto II lost his power after some financial disagreements he had with the Emperor and later he died of epilepsy. In 1329 A.D. Chios was liberated by the family of Zacharias, but unfortunately not for many years.