The Hagia Sophia anchors Istanbul’s Old City and has acted as a beacon for both Orthodox Christians and Muslims for centuries, as its importance has changed with the prevailing culture in the Turkish city. Istanbul is located on both sides of the Bosporus Strait, a waterway that connects Europe and Asia. Thus, the Turkish metropolis of over 15 million people is located on two continents.

History of Hagia Sophia in Turkish Reign

The Hagia Sophia (Ayasofya in Turkish) was constructed as a basilica for the Greek Orthodox Christian Church. However, its role has evolved many times throughout the ages. In 360 A.D., Byzantine Emperor Constantius commissioned the building of the first Hagia Sophia. Istanbul was known as Constantinople at the time of the first church’s construction.

During the Crusades, Constantinople and, by extension, the Hagia Sophia were briefly under Roman authority in the 13th century. During this time, the Hagia Sophia was badly damaged, but it was restored when the Byzantines reclaimed control of the surrounding city. The Ottomans, headed by Emperor Fatih Sultan Mehmed—known as Mehmed the Conqueror—captured Constantinople in 1453, ushering in the next major era of development for the Hagia Sophia. Istanbul was renamed by the Ottomans.

Renovations of the Hagia Sophia

Because Islam was the Ottomans’ primary religion, the Hagia Sophia was converted into a mosque. Many of the original Orthodox-themed mosaics were covered with Islamic lettering created by Kazasker Mustafa Izzet as part of the conversion. The panels or medallions placed on the nave columns bear the names of Allah, the Prophet Muhammad, the first four Caliphs, and the Prophet’s two grandsons. The main dome’s mosaic, which is thought to represent a picture of Christ, was also covered with gold calligraphy.

During this time, four minarets were built to the original construction, partially for religious reasons (for the muezzin call to prayer) and partly to strengthen the edifice after earthquakes that rocked the city around this time. Between 1847 and 1849, under the reign of Sultan Abdülmecid, the Hagia Sophia received major renovations supervised by Swiss architects the Fossati brothers, next to the Blue Mosque. The Hünkâr Mahfili (a separate chamber for emperors to pray in) was dismantled during this period and replaced with another near the mihrab.

Hagia Sophia Today

Even now, some 100 years after the Ottoman Empire‘s demise, the Hagia Sophia’s position in politics and religion remains controversial and significant. The famous building was maintained as a museum by the national government from 1935—nine years after Ataturk founded the Republic of Turkey—to 2020. Beginning in 2013, certain Islamic religious leaders in the nation attempted to reopen the Hagia Sophia as a mosque. The Turkish Council of State and President Erdogan categorized it as a mosque in July 2020.

Recent Changes at Hagia Sophia in 2024

Starting from January 15, 2024, visitors to Hagia Sophia will encounter significant alterations. A nominal entrance fee of 25 euros has been implemented, replacing the prior free admission policy. This fee provides access exclusively to the 2nd-floor visitor areas, with entry to the prayer area restricted. Notably, guided tours are no longer permitted within Hagia Sophia. It’s essential to anticipate potential queues, given the revised visitor capacity. Despite these adjustments, the timeless magnificence of Hagia Sophia remains accessible for exploration.

Istanbul Throughout History

Istanbul is one of the world’s most significant cities, with a history reaching back to 660 BCE. Istanbul began as an ancient Greek city called Byzantium, was known as Constantinople during the Roman and Byzantine periods, and was known as Konstantiniyye and Dersaadet under the Ottoman Empire. Only since the republic era has the city been legally known as Istanbul. 

Istanbul’s official history goes back to 2700 years ago, and its historical depth is too great even for the people who live there, much alone tourists. As a result, a few days in Istanbul will not enough to understand its past.

Hagia Sophia (Holy Wisdom Cathedral)

The Hagia Sophia was constructed in the aftermath of the Nika Revolt, which destroyed many of the city’s structures. Emperor Justinian survived the revolt that killed 30,000 people, and he started to construct magnificent structures to restore his image. Thus, Anthemius and Isidore, appointed by the Emperor, constructed the world’s largest and most magnificent sanctuary. 

Built in 537, Hagia Sophia was such a magnificent architectural masterpiece that it took 1000 years to create buildings comparable to it. Such monuments first appeared in Europe during the Renaissance. And in the East, one thousand years after Hagia Sophia, Mimar Sinan constructed mosques that might be compared to Hagia Sophia. 

Basilica Cistern

The Basilica Cistern is one of Istanbul’s most intriguing locations. When you visit this cistern, which is now a museum, you will undoubtedly get chills. 

In its lengthy history, Istanbul has been subjected to many sieges. Constantinople was one of the most beautiful capitals in the Middle Ages, with a wealth that drew different civilizations and barbarian tribes. 

The renowned Constantinople Walls were constructed in the 5th century and protected the city for centuries. Only two times in history has the city defense failed: the Sack of Constantinople and the Fall of Constantinople. 

Hippodrome In Istanbul

The Hippodrome, situated in the center of Sultanahmet, is where chariot races were held in front of 50,000 spectators in Constantinople, the capital of the Byzantine Empire. Chariots were two-wheeled vehicles drawn by four horses, and riding these chariots required a tremendous deal of expertise. The chariots would speed on the even section of the track and then slide severely around the curve, putting riders’ abilities to the test. 

The Emperor would watch the races from his lodge, and these races would also see some significant occurrences. The Nika Revolt, Istanbul’s largest revolt, began here and swept across the city. Little remains of the Hippodrome’s former grandeur. Even the surviving Theodosius Obelisk, Serpent Column, and Walled Obelisk had a long history. The Obelisk of Theodosius, a 3500-year-old obelisk imported from Egypt, is Istanbul’s oldest historical monument. 

Forum Of Constantine

The Forum of Constantine was one of Rome’s earliest famous structures. This plaza, built by Constantine the Great, served as the heart of Constantinople. During Emperor Constantine’s reign, the city’s main thoroughfare was known as “Mese.” The triumphant Roman troops returning after a war would march along this street, which also contained the Forum of Constantine. Today, this plaza is known as “Cemberlitas,” and it has a porphyry column built by Constantine. 

The center of Byzantine Istanbul was two squares. The Forum of Constantine was one of them, while the Forum of Theodosius was the other. Mese is still a major thoroughfare in the Old City, and it is known as “Divanyolu Street,” down which the tram travels. Divanyolu Street was called under the Ottoman Empire because it led to the Divan-i Humayun (Imperial Council) at Topkapi Palace.

For this reason, the Roman Empire and the Byzantine Empires gave the necessary value to Istanbul. Developed and grown by the Roman emperor Constantine, Istanbul was known as Constantinople. After the collapse of Western Rome, it began to host the Eastern Roman, that is, Byzantium. In the research about Istanbul, we see those empires such as the Byzantine Empire and the Ottoman Empire cherished Istanbul and evaluated it as the capital. However, in today's Turkey, Istanbul is not a capital city but a metropolis.

First Civilizations in Istanbul

If we are talking about the history of Istanbul, we must speak of the Roman and Byzantine empires. Still, according to the research, it has been proven that there has been life in Istanbul since the polished stone age, but it is accepted that the Megarians carried out the known provincial settlement. According to the first recorded information in the post-historical period, the ancient Greek city-state was one of the first owners of Istanbul. 

Istanbul, which later came under the rule of the Roman Empire, is the apple of the eye of the Republic of Turkey today, after the domination of the Byzantine, Latin, and Ottoman empires, respectively. For this reason, Istanbul is a world city that attracts attention with its beauty and geographical location. What can be deduced from this is that Istanbul is an important city, both politically and socially, regardless of who is under its rule.

Places to Witness the History of Istanbul

Undoubtedly, the best way to get extensive information about Istanbul is to visit the historical museums or places in Istanbul. In our opinion, the first example that can be given would be to visit Hagia Sophia, which used to be an Eastern Roman church. Again, the Maiden's Tower, located in the Bosphorus, should be at the top of the list with its historical structure and magnificent attitude.

In addition, the Galata Tower, one of the important works of Istanbul, was built during the Byzantine period and is a must-see. In addition, the large palace mosaics museum, which is also one of the works of the Roman period, will also serve as a good compass and will make your trip much more enjoyable. Binbirdirek Cistern, also a work of the Constantine period, is among the places to be seen. In addition, the Archeology Museum, which will serve as a treasure trove of the history of Istanbul, is a very productive resource.

Last but not least, one of the places that can be said to be the first place to be seen in Istanbul is the Basilica Cistern, which is known for storing tons of water. In addition to all these, the Theodosius obelisk and Bozdoğan Kemer are the Byzantine period works that should be seen. When these artifacts are visited, it will be possible to reach a wide range of information about Istanbul and the Roman and Byzantine Empires.

Stories of Legendary Places in Istanbul

The Maiden's Tower mentioned in the examples we have given was strengthened during the Byzantine Empire and used for different purposes for centuries, but it has a sad legend. The legend is that a young man named Leandros secretly meets his lover named Heros in this tower. One night, when he sees the light on the tower, he thinks that his lover sent him a sign, and he goes to the tower in the middle of the sea, but this time he is on the board because someone else who knows these secret meetings has turned on the light and turns it off after a while. Therefore, Leondras dies, and his lover leaves herself in the cold waters of the sea. In addition to this sad legend, there is a legend of the Galata tower, which is a Roman structure. 

According to Roman belief, a couple who climbs the Galata tower will marry and live happily ever after. Still, if these couples are not destined to meet, they will always encounter an obstacle and cannot get married. In addition to all these legends, there is another common legend of Galata and Maiden's Tower, which is related to the possibility that Galata Tower and Maiden's Tower are in love with each other. However, Bosphorus is an obstacle for lovers to meet. However, it is believed that it helped them to continue their passion for the Bosphorus, that Hezerfen Ahmet Çelebi, who had a dream of flying with wings, carried their letters to each other, and that's why these two towers create a wonderful harmony. All these legends aside, we strongly recommend you visit these places, which we believe will fascinate you both historically and visually.

Beyond its architectural marvels, Constantinople was a hub of intellectual and artistic pursuits. Its scholars and artisans produced groundbreaking works in philosophy, science, and art, influencing the development of European civilization. The city's libraries and universities attracted scholars from across the known world, fostering a vibrant intellectual atmosphere. Constantinople's legacy extends far beyond its physical remains, shaping the course of history and leaving an enduring mark on the world.   

Establishment and Byzantium Period

The history of Istanbul began thousands of years ago. But, firstly, Megarians were the settlers in Istanbul in the 7th century B.C.E. Megaran was a city-state in Ancient Greece. Byzas, king of Megara, wanted to establish a new city-state, so he went to the Temple of Apollo and consulted an oracle. Oracle said “You should establish against the country of the blind.” Byzas was confused. While he was walking, he looked at Kadiköy from Sarayburnu. He thought that while this area was more remarkable, why did people find a city there? Anyone, who founded a town there, must be blind. And he decided where to establish the city. And Megarians founded a city in 667 B.C.E. The city’s name was Byzantion. Byzantium is the first name before Constantinople and Istanbul.

Roman Empire Period of Constantinople 

Byzantium continued as an ordinary and unimportant city till the 4th Century. However, Byzantium started to be important because of its location after Constantine became the emperor of the Roman Empire. 

Constantine was important to the history of Istanbul as Constantine considered moving the capital to another city. He considered Izmit, Troy, and Byzantion, and he chose Byzantion because it sat at the end of important trade routes. Also, Byzantium was built upon the land of seven hills like Rome. The city became the capital city 65 years ago before the Roman Empire separated. The city was mentioned as Constantinople after Constantine’s death. 

In the Constantine period, the city began to change and develop. Constantine didn’t ruin the city. He designated town borders. Constantine got the palace done for people who came from Milano. Hippodromes were built, and walls started to be renewed in Constantinople. We can say that the history of Istanbul was initiated in this period.

After Constantine’s death, the Emperors continued developing the city. During the Theodosius Period (379-395), he built a harbor to find a solution to the food problem. He got the warehouse done. Forum Tauri, now known as Beyazid Square, was built in this period. In 395, the Roman Empire was split into two parts East-Rome and Western-Rome. Western Rome’s capital city became Milano, and East- Rome’s capital city, was Constantinople. The city was built as a city for Christians after Emperor Theodosius signed the edict of Thessaloniki. In time, the city became the center of Christianity.

Constantinople continued to improve and change in the II. Theodosius Period. Walls extended and cultivated areas, and structures were put under protection. During this time, Constantinople reached its most magnificent state. The situation continued until the Roman Empire collapsed. In the 465 Emperor Leon period, a fire started in Constantinople, and it destroyed half of the city. After the fire, the city began to renew. But in the Justinian I Period, Nika riots began, and the civil commotion ruined the city again. Justinian I suppressed the Nika Riots, and he started to design new architecture, and he decided to build a new Church. The Church’s name was Hagia Sophia. He built the Basilica Cistern and the Binbirdirek Cistern. And he changed the official language to the Helen language. 

After Justinian I, the unproductive period started in the Roman Empire. But constructions started again in Constantinople in Theophilos and Basileios I Period. Churches and monasteries were built in this period. Many of the buildings still are in Constantinople.

The Latin Occupation: A Dark Chapter in Constantinople's History

The Fourth Crusade, initially intended to liberate Jerusalem from Muslim rule, took a devastating turn when it was diverted to Constantinople. In 1204, a Crusader army, primarily composed of Venetian and French forces, laid siege to the city, ultimately sacking and occupying it. This marked the beginning of the Latin Empire, a short-lived Western European state that ruled over parts of the former Byzantine Empire.

During the Latin occupation, Constantinople suffered immense destruction. The city's renowned Hagia Sophia was desecrated and converted into a Roman Catholic cathedral. Countless priceless artifacts and relics were looted and dispersed across Europe. The city's once-thriving economy and cultural life were shattered. The Latin Empire's rule, however, was ultimately short-lived. In 1261, the Byzantine Empire, under the leadership of Michael VIII Palaiologos, reclaimed Constantinople, marking a significant turning point in the city's history.

The Byzantine Empire After the Latin Occupation: A Period of Decline and Resilience

The recapture of Constantinople by Michael VIII Palaiologos in 1261 marked a significant turning point, but the city had been irrevocably scarred by the Latin occupation. The once-glorious metropolis was diminished, its wealth plundered, and its infrastructure damaged. Despite the Byzantine Empire's efforts to restore its former glory, it faced numerous challenges, including internal strife, economic decline, and external threats.

The Ottoman Empire, a rising Islamic power, posed the most serious threat to Constantinople. Over the centuries, the Ottomans gradually expanded their territory, encroaching on Byzantine lands. The city itself was besieged multiple times, with each siege testing its defenses and resilience. While the Byzantines managed to withstand these attacks, the empire's gradual weakening made it increasingly vulnerable.

The Ottoman conquest of Constantinople in 1453 marked the end of the Byzantine Empire and the beginning of a new era for the city.

The Ottoman Conquest: The Fall of Constantinople

Despite the setbacks and challenges faced by the Byzantine Empire, Constantinople remained a formidable fortress. However, the rise of the Ottoman Empire posed a significant threat to the city's existence. In the late 14th and early 15th centuries, Ottoman sultans, including Bayezid I and Murad II, attempted to conquer the city but were thwarted by various factors, such as internal conflicts and external pressures.

The turning point came in 1453, when Sultan Mehmed II, known as Mehmed the Conqueror, laid siege to Constantinople. After a grueling 53-day siege, the Ottoman forces breached the city's defenses, conquering it on May 29, 1453. The fall of Constantinople marked the end of the Roman Empire and ushered in a new era for the city. Under Ottoman rule, Constantinople underwent a significant transformation. The Hagia Sophia was converted into a mosque, and the city became the capital of the Ottoman Empire, serving as a cultural and economic center for centuries.

The Ottoman conquest of Constantinople was a significant turning point in the city's history. Mehmed II, also known as Mehmed the Conqueror, recognized the city's strategic and cultural value. He implemented policies to revitalize Istanbul, making it the capital of the Ottoman Empire. The city was transformed into a cosmopolitan center, attracting people from various ethnic and religious backgrounds.

One of the most significant changes under Ottoman rule was the conversion of the Hagia Sophia, a former Byzantine cathedral, into a mosque. This iconic structure became a symbol of Ottoman power and Islamic architecture. The Ottomans also constructed numerous mosques, palaces, and other public buildings, adding to the city's rich architectural landscape.

The Ottoman period saw significant economic and cultural development in Istanbul. The city became a hub for trade and commerce, connecting East and West. Its bazaars and markets were renowned for their diverse goods and vibrant atmosphere. The Ottoman Empire's patronage of arts and sciences also contributed to Istanbul's cultural flourishing.

However, Istanbul, like any great city, faced its share of challenges. Earthquakes, fires, and wars took their toll on the city's infrastructure and population. Despite these setbacks, Istanbul's resilience and enduring appeal allowed it to emerge stronger.

The Ottoman Empire's decline in the 19th and early 20th centuries led to significant changes in Istanbul. The city's cosmopolitan character was challenged by rising nationalism and political instability. However, Istanbul's historical and cultural heritage remained intact, ensuring its continued significance in the global landscape.

The Golden Age of Ottoman Architecture: The Era of Süleyman the Magnificent and Sinan

The reign of Süleyman the Magnificent (Süleyman the Lawgiver) marked a golden age for the Ottoman Empire, including Istanbul. Known for his patronage of arts and sciences, Süleyman commissioned numerous architectural projects that transformed the city's skyline.

A key figure in this era was the renowned architect Mimar Sinan. Under the patronage of Süleyman, Sinan designed and built some of Istanbul's most iconic structures, including the Süleymaniye Mosque, the Şehzade Mosque, and the Süleymaniye Complex, which included a mosque, madrasas, a hospital, and a tomb. These structures are renowned for their grandeur, intricate details, and innovative architectural techniques.

The Suleymaniye Mosque, in particular, is considered one of Sinan's masterpieces. Its imposing dome, graceful minarets, and spacious courtyard have made it a symbol of Ottoman power and Islamic architecture. The complex also includes a library, a hospital, and a tomb, demonstrating the Ottoman Empire's commitment to education, healthcare, and religious piety.

The legacy of Süleyman the Magnificent and Mimar Sinan continues to shape Istanbul's identity. Their architectural works not only beautify the city but also serve as a testament to the Ottoman Empire's cultural and artistic achievements.

The Ottoman Empire After Süleyman the Magnificent

The Ottoman Empire continued to thrive after the reign of Süleyman the Magnificent, though the empire gradually entered a period of decline. However, Istanbul continued to be a center of art, culture, and architecture. 

One of the most iconic mosques built during this period is the Sultan Ahmed Mosque, also known as the Blue Mosque. Renowned for its stunning blue Iznik tiles, the mosque is a masterpiece of Ottoman architecture.

The Tulip Era, a period of cultural and artistic flourishing, saw the construction of numerous gardens and pavilions in Istanbul. The city's landscape was transformed with new architectural styles influenced by European trends. The construction of the Ahmet III Library in Topkapi Palace further enriched Istanbul's cultural heritage.

The 19th century marked a significant turning point for the Ottoman Empire, as it embarked on a series of reforms known as the Tanzimat Era. The Tanzimat reforms aimed to modernize the empire and align it with Western powers. This led to the introduction of Western-style architecture, infrastructure, and education systems. 

After the collapse of the Ottoman Empire and the establishment of the Republic of Turkey in 1923, Istanbul continued to evolve. While it lost its status as the capital, it remained a vibrant city and a major cultural and economic center. 

Today, Istanbul stands as a testament to its rich history and diverse cultural heritage. Its historic sites, such as the Hagia Sophia, Topkapı Palace, and the Blue Mosque, attract millions of visitors each year. The city's blend of ancient and modern, East and West, makes it a truly unique destination. 

Excavations conducted at Yarımburgaz cave have uncovered evidence of human culture in the region of Küçükçekmece Lake. Collective inhabitation of Istanbul, which would later become one of the most crowded cities in the world, dates back to the Sixth Millennium B.C.E. These societies inhabited caves on both the European and Anatolian sides of the city.

While the first societies to exist in the area of Istanbul were nomadic and semi-nomadic, more culturally-developed groups -whose livelihood relied upon fishing, agriculture, and animal husbandry- emerged over time. Research conducted at Fikirtepe has shown that these societies engaged in fishing and raising such animals as dogs, sheep, goats, oxen, and pigs from the Sixth Millennium B.C.E. onward.

Forming The City

With the arrival of the Third Millennium B.C.E., settlement in Istanbul and the surrounding areas grew rapidly, and city-states began to form. Throughout the area’s entire history, and particularly during this era, the area near Sultanahmet Square—which would later become the seat of three different empires—was an important focus of settlement.

The first societies to reside in and around Istanbul—which is today such an important economic center in the global arena—were nomadic and semi-nomadic. In the Third Millennium B.C.E., after the establishment of permanent settlements, Sultanahmet Square and the area nearby became an important center of growth.

Mustafa Kemal Atatürk in the War of Independence

As a result of the modernization process that has characterized Turkey’s Republican history since its beginning, Istanbul has developed an identity as a modern, global city that is unique to itself. From an economic and cultural perspective, Istanbul is the heart of contemporary Turkey. Due to the city’s unparalleled historical heritage, it continues to be a uniquely important city, not only for Turkey, but also in the eyes of the world as a whole.

Istanbul, which is home to many international political, cultural, fine-arts and sports organizations, is rapidly climbing toward the most elite level of world cities. As a unique synthesis of east and west, Istanbul is home to all of the colours of a world that no longer exists within borders. Istanbul, Turkey’s open door to the West, has redefined its former status as an imperial capital through becoming a world-class centre of trade, business, tourism and culture.

Republican period and new istanbul

Losing The Capital Title

Istanbul, which was a capital to three great empires, left this title to Ankara. The population, which was around 850 thousand at the turn of the century, decreased to 700 thousand in the population census of 1927 with the turn towards Republican Period. 

While the efforts for westernization were shifted to Ankara in cultural, political, economical, architectural and ideological respects, Istanbul was seriously neglected. And Istanbul, in its history of over two thousand years, started to be governed from the outside for the first time. Much less resources than it produced were allocated to the city, which continued to be the economical and commercial center.

In this period, no work was done with regards to urban planning. There were only changes which reflected the ideology of the fresh state; changing of the street names, allocation of buildings of Ottoman dynasty and empire for new functions, St.Sophia’s turning into a museum, imperial organizations being opened to service with new names and purposes were mere symbolic activities during the period. 

First Moves Of Urban Planning

The first moves regarding Istanbul’s urban planning started when Adnan Menderes, leader of the Democratic Party, was in power. Social movements starting after the 1950s and a population explosion resulted in frantic architectural growth in Istanbul. The modern city image devised by Democratic Party executives added to the development. The roads, which were launched to service in spite of the destruction of the historical city, changed the fabric of the city.  

Between 1950 and 1960, many main highways were opened to public service and already active ones were expanded. When those roads were being opened to public service, thousands of buildings were demolished. Many historical sites were damaged. Many works of art were either transferred or destroyed. Also in this period major buildings were constructed which reflect the change in city’s architectural canvas such as the Municipality, Hilton Hotel and Divan Hotel. 

Between the years 1950 – 1960, Istanbul did not undergo any notable urban planning. This did not occur until the 1970s, after the urbanization works in Democratic Party period were long entrenched.

Bosphorus and Fatih Sultan Mehmet Bridges

In 1973, Bosphorus Bridge was opened to service. The Bosphorus Bridge, with its surrounding approach ways, caused the emergence of new settlements and new fields of profitability in the neighborhoods of the metropolis. 

After the 1980s, a second settlement plan was put into action, though it was not as comprehensive as the first. The clearance of industrial institutions from The Golden Horn, the opening of Fatih Sultan Mehmed Bridge in 1988 as the second bridge over Boshporus, Tarlabaşı Boulevard, piled road in European side of Bosphorus, the coast between Kadıköy and Bostancı’s being filled and turned into a highway, express tram, and a metro project between Taksim-Levent were the major works in this plan. Also in those years, the migration to Istanbul increasingly gained speed. The city was surrounded by shanty towns and cheap cooperative houses. 

The 1980s saw industrial institutions moved out of the city. Thanks to the popularization of the natural gas network and meticulous controls in coal consumption, residents of Istanbul lived a winter of tranquility regarding air pollution. Also, the water supply problem, one of the most troubling issues of the city, was handled for the most part as a result of the employment of new facilities of water supply and new investments on water softening and its distribution.

On October 9, 1920, Turkish soldiers entered Izmir’s boundaries led by supreme national leader Mustafa Kemal Atatürk. This event started the independence process for Istanbul. With the Mudanya Agreement signed on October 11, it was agreed that the invading forces would leave Thrace gradually. The Turkish Grand National Assembly that convened in Ankara declared the Ottoman dynasty be abolished in November 1, 1922. Therefore, even though Istanbul remained the legal capital until October 1923, it was no longer the actual capital. On November 16 Sultan Vahdettin left Istanbul.

In November 4, 1923, Istanbul was completely free of invading forces. Therefore, the second invasion of Istanbul by Europeans after the Latin invasion of 1204 was terminated.

This rapid westernization activity left its traces in architecture as well. In this period, classical Ottoman architecture was abandoned and new buildings were made in western styles such as baroque, rococo, neogothic and ampire. Indeed, this change in style penetrated into the architecture of mosques as well.

In those years, there were notable improvements in infrastructure and urban services. These include the building of a bridge over Golden Horn, tunnel (subway), Rumelian Rail, launch of Şirket-i Hayriye that administered in-city sea transport, establishment of other state offices of Şehremaneti (Municipality), hauling of the first telegraph line, establishing of Police Force Directorate and the police stations under its control, servicing of Vakıf Gureba Hospital and Horse-Drawn Tram Company.

A great importance was given to the opening of modern educational institutions that would nourish the process of westernization. Darülfünun, the foundation of today’s University of Istanbul, men’s and girl’s high schools, School of Architecture, School of Telegraph Information, College of Education, Teachers High School, School of Forestry, School of Nursery and Midwifery, Mekteb-i Sultani (Lycee of Galatasaray), School of Industry and School of Medicine and State Administration were the schools which started their education period then.

During Kanuni Sultan Süleyman’s period, Istanbul became a more organised city. In one respect, new migrations were prevented, and also construction of houses around walls was prohibited and it was obligated that every house had a shutter over windows and stone construction was to be used in every building in Galata.