Syros could not differ from the other Cyclades Islands with the rich history that has its sources in very old myths, but also historical elements that combine with through out the centuries.

The most ancient myth referring to the island of Syros, is the one of Coiranos. This myth is referred to the homonym king of the island who probably lived during the fist historical years, had been shipwrecked openly of the shores of Paronaxia and was saved by a dolphin that carried him on his back till Syra. He was a man gifted with great virtues and abilities that made him lovable and respectable to all Syrians who honored him for many years in the cave where he first arrived after his sea adventure. The Coiranian Cave.

There is also a reference in Rapsody O of Homer's Odyssey and specifically at the line where Evmaios the swineherd, narrating to Ulysses, refers to Syriyn island (considered probably as Syros Island of nowadays) where king was Ktisios the Ormenides, the swineherd's father. From the whole description, if truly the island by the name of Syriyn corresponds to Syros island of nowadays, then this is the oldest script historical reference about the island.

Phoenicians are considered the first habitants of the island and had a great influence on many social and religious matters. For example, in the island they worshiped the god Panas, whose cult had directly its origins on Egypt.

Archaeological excavations in several places of the island, revealed significant findings and traces of cycladian civilization of the first Period, leading to the end of Neolithic Era and the beginning of the Bronze Age. Indicative places that had been inhabited during that period is the Xontra peninsula and the spot Koskinas at the area of Vari as well as the spot Agia Thekla above the village of Chrousa.
The little idols of this period are of great interest, representing women with heads in the shape of lyre, the anatomic details of their bodies very little curved and their hands crossed below chest while the knees are slightly bended.

The Cycladian Civilization had grown in Syros until the first half of the 2nd millennium BC and reached very high levels. We have indications and findings of this period in the areas of the island Chalandriani and in Kastri of Epano Meria too. From the studies made upon the findings of these two specific areas, it is considered that during that period there had been a great increase of population as well as elements of agricultural societies and also of fishermen. Also, there was intense cultural activity and increasing contact with the outside world. Also, during this period took place the construction of fortifying settlements near the sea and at wealthy areas, but also an exploration of naval presentation of the inhabitants of the island in Aegean Sea, which enlarged the horizons and the development of handicraft and commerce.

During the 6th century BC, Ionians appear to the island. At that period, the island lives a special prosperity as the democratic state is established and reinforced.
At this period is born in Syros philosopher Pherekydes, considered one of the pioneers of pre-Socratic thought and philosophy, Pythagoras's teacher and inventor heliotrope, a kind of sun clock.   
His life was also unbreakably related to the Greek cities of Asia Minor, since he vividly participated in the mental movement of Ionian philosophy.

In 490 BC until the sea battle of Salamina, the island is conquered by Persians. After that, Persians have been chased out of Cyclades while Athenians formed the Holly Alliance in which Syros participated with conditions favorable enough for its further development. It is somehow organdies the safety of the island from the invaders, fact that prove the remainings of castles and watchtowers sited on strategic spots. There is on Vouli island almost identical to the Athenian one as well as indications that Syrians had social organization according to the Athenian models. There was also an Asklipieion and a Mint.       
After the battle at Haironeia on 338 BC, Syra was conquered by Macedonians. About the end of 2nd century BC, the island becomes a significant junction of the Aegean Sea living at the same time a great commercial activity, while the coins of that period coming out its Mint circulate even in Syria. At the same period, the second big city at Galissos is abandoned and Ermoupoli becomes ever since the center of the island.  
The Rroman Dominion that followed, not only had not held the development of the island, but contributed to its prosperity instead. The commercial importance of its port launched to heights while the various roman emperors'interest in the island was obvious as the numerous findings of this era prove.  
Along with the end of the ancient world, is noticed a turn of life towards the country, as it is indicated by various and numerous establishments of the 3rd century BC in midlands. 
On 4th century, Syros adopts Christianity, while at the same time begins a turbulent era (that lasted almost 900 years), characterized by predatory invasions of pirates, Arabs, Slaves and Saracens.

In the beginning of the 9th century AC, is created the sole naturally fortified settlement of the island visible from the sea, «the Rock» the Ano Syra of nowadays, by the hunted Syrians expelled by the Saracens'invasions.  
At this period, the island is part of the Byzantine Thema of the Aegean Sea and ecclesiastically belongs to the Bishopric of Delos and afterwards to the Bishoprics of Athens and of Kea-Thermia and Serifos.

In 1207 and the catalysis on Byzantium, the island along with most of the Cyclades Islands comes in the hands of Venetians and becomes member of the Dukedom of Aegean Sea under the dominion of Marcus Sanudus, with the island of Naxos as capital. 
The Venetians, during their dominion, tried to impose the feudal administrative and economical system, but they failed, while at the same time Catholicism was consecrated and admitted by Syrians, without negative consequences on the Greek language or the habits and customs of the island.
The proof of this is the preservation of plenty ancient toponymies as well as the survival of orthodox worship models and the presence of local orthodox feasts in the holiday-calendar of the island.   
The Venetian dominion was sealed by perpetual conflicts among Franc rulers who claimed the dominion of the island for their own interest, as for example the siege of the island on 1286 by Bartholomew Gyzis, the Duke of Tinos Island. Also, the violent piratical invasions left ineffaceable marks although the island was favored with the protection of the west forces and especially with the one of Roman Catholic Church. Through out this period, the island has always been part of the Dukedom of Aegean Sea whose the main duty was collecting taxes. Also, at the same period, the catholic clergymen had a great political and economical power on the island.

The end of Franco Venetian dominion on Syros comes in 1537 AC because of Turkish prevalence in Aegean Sea. The Turkish administration in the island is strictly limited in tax collection while the self-government has been developed. The island suffered continuous predatory invasions by franc pirates who were in permanent conflict against the Turks. The consequence was that the habitants were exposed many times in difficult situations. For example, on October 1617, Captain Ali Pasha, considering the habitants accomplices and conspirators against the Turkish Empire with headline Andreas Kargas, Bishop of Syros, proceeded to the decapitation of the late and the extinction of great part of local population.

The two Turkish Venetians wars that followed, forced the habitants to leave the island and thus, inevitably, there has been a dramatic decrease of the population. Though Syros was one out the 5 islands (of the total 16 islands) of the Dukedom of Aegean Sea that remained habitable those difficult years. 
In1633 the French monks establish in Syra and they found the French Capuchin's Monastery of as well as a school.

In the years that followed and about the end of 17th century, the local administration and the judicial authorities became a little bit more loose and beneficial for Syros.   
There have been legislated implements for local administration such as the people's assembly, the headmen and the procurators. In the first team participated all male up to 30 years old, while the assembly gradually gained legislatively competences. The headmen were elected by the assembly once a year, they had administrative competences and their validation came directly from the Sublime Porte. The headmen were old procurators elected again by the assembly and they participated in the judicial and administrative activities of the island.

In 1680 the Community of Syra discharged the port of the island, by particular decision, from any kind of taxes, founding thus the basis for establishment and development of commerce. At the same time, Turks did not live on the island while the Turkish Kadis (judge), responsible for Syros, dwelled in the island of Andros. The Bishop was named by the Pope, while French had gained a great influence and had detached from the Turks many privileges for the Syrians monks and clergymen.
The consequence of all these was the creation of security and economic prosperity factors for the island that proceeded to the gradual increase of its population. According to witnesses, on the second half of 18th century there were more than 2500 habitants. They were almost all Catholics except a few orthodox ones. In the island had begun an intense cultivation and the young people had started to study in schools and universities of Italy always under Pope's aegis.        
This ascending course of the island was abruptly stopped by a cholera epidemic in 1728.

In 1771 during the Russian Turkish wars, along with the other Cyclades, Syra was occupied by the Russians too. Under the Russian dominion (1770-1774) the taxation in the island had been doubled (in goods and money) being unbearable.
With the participation of the Russian Admiral there had been severe losses of significant archeological treasures of the island.  
The island was regained by the Turks and thanks to the great contribution of Stefanos Mavrogenous, Captain Ali Pasha's Parian interpreter, (afterwards ruler of Vlahia and also Manto Mavrogenous's father) the reprisals were avoided. In addition, Syra during the period 1779-1803 was under the jurisdiction of the Sultan's niece Sah who assigned to the island many privileges and financial reductions.

In 1814 is recorded in Syra the first riot on taxic basis in the beginning. The sequence was the overthrow of the favorable system of local government and the capture of strategic positions in dominion by the wealthy bourgeoisie of Castro who were placed in community government as representatives of the low classes.   
At this period, the piracy reduces well enough and about 1820, when the navigation towards Eastern Mediterranean Sea was secure, the island taking advantage of its geographical position, of the everlasting support of the western forces and of the reinforced local self-government, is rapidly developed to a great nautical junction. The island returns to life. At exactly this moment, comes the great revolution of 1821.
The truth is that the island received a great wave of refugees from the destroyed islands of Chios (1822) of Kasos and of Psara in 1824. It must be mentioned that the element of refugees was absorbed and managed to contribute to the development of the island in a direct and effective way. The inhabitants of the island, basically sailors and merchants, dwelled in the beginning in some ready made sheds around the physical port of the island. Little by little a new city emerged around the port, while at the same time the neutral status the island had held towards the Revolution, in accordance with France, was overthrown since 1823 the authorities take officially place that is announced to the National Assembly and is ever since under the Greek government while is already part, along with the island Mykonos, of a particular Greek province founded one year ago.
From the moment that Syros stands in favor to the Revolution, the French influence starts to diminish as well as the one of catholic element in the facts of the island. As time went by and in the beginning of 1826, the scattered settlement of refugees around the port had turned out to become an urban settlement in full flourish and ascending development.  
Ermoupoli worthily becomes then the center of the island. After the declaration of independence of the Greek State in 1828, becomes the capital of the province of North Cyclades, with population up to 13.805 habitants. Thus, the city along with its quickly ascending financial and popular growth develops to an upcoming administrative and cultural centre of the New Greek status.    
After Othon's arrival in Greece and the new regime he established, Ermoupoli becomes the capital of the whole county of Cyclades and the head office of the Bishopric of Cyclades. Finally, it is fully organized as the center of administrative and juridical authorities.

After the establishment of the Greek State, the flourishing of the island and especially of Ermoupoli, is an undisputed fact. Its port is organized, the dock is constructed as well as the first in Greece public transit warehouses, while at the same period (1834-1842) develops a great shipbuilding activity since the official sourced refer that about 60-80 ships a year were built in the island of total capacity more than 130.000 tons .  The private shipyards are flourishing Famous craftsmen work in those coming from different places, as Chios, Psara, Hydra and Spetses.  It is speculated that about 2000 workers were working in the shipyards of the island in 1835.
In the years that followed, its port is filled up with commercial ships from every nationality and in the island are established the first in Greece industrial enterprises. For example, the Tanneries of Syra, famous as the best in the East, the first flour industry in 1861 and a little bit later many spinning-weaving factories. We must also mention the creation of the workers' trade unions and the commercial and industrial unities. 
In 1879 takes place the first strike in the shipyards and in tanneries.
All these changes appearing for the first time in the Greek facts have a significant influence on the sociopolitical synthesis as well as the educational and cultural section of the island. While the private schools flourish, many children from all over Greece study in the Gymnasium of Syros, nautical schools are also founded, the Religious Seminary of Cyclades, schools of education for the working people, schools for poor children and women and many other schools that gain nationwide reputation.

Since the first years of existence of Ermoupoli, the theater also makes its appearance. It is organized little by little reaching its pick with the construction of Apollo Theater in 1864.  It is a building jewel for the city and is even characterized as the micrography of the Scala at Milano. Another important element of the cultural evolution of Syros consists, without doubt, the foundation of many publishing houses and local newspapers with rich news editing contents. Syros soon gains intense political consciousness and interferes energetically in the facts of Greece. It participates in the fights for the protection of the Constitution in 1862, while after the explosion of Cretan revolution volunteers and becomes the main basis of material and moral support to the Cretans fighters. Since 1852-1922 Syros received a great wave of Greek refugees and became for them a new home. In 1889 reaches the number of 31.573 habitants and faces the most crucial turn of its history.

The economy of Syros began to stagger about the end of 19ου century, because of the evolution in the international commerce, the shipping and the industry. Plus, with the systematical removal of the center of the Eastern Mediterranean trading traffic from the island, begins little by little its financial decaying. In 1900 many factories were already closed or were about to be. The consequence of this was the diminish of the population after 1910, when it happens a migrating wave to other countries during the period between the two world wars, especially of the wealthy classes. 
The German occupation however, brought the final decay of the financial and social life of the island. The epidemics sole and the pitiless bombarding of 1941 caused a great loss of its human resources. Many claim that no other provincial city had suffered so much during those dark years as Ermoupoli.

Though the island had lived many social and financial changes through out the years, Syros managed to maintain a high living level and the memories of most vital and significant past till nowadays.