Throughout most of its history, Istanbul has ranked among the largest cities in the world. By 500 CE, Constantinople had somewhere between 400,000 and 500,000 people, edging out its predecessor, for world's largest city. Constantinople jostled with other major historical cities, such as Baghdad, Chang'an, Kaifeng and Merv for the position of world's most populous city until the 12th century, it never returned to being the world's largest, but remained Europe's largest city from 1500 to 1750, when it was surpassed by London. The Turkish Statistical Institute estimates that the population of Istanbul Metropolitan Municipality was 14,377,019 at the end of 2014, hosting 19 percent of the country's population. About 97–98% of the inhabitants of the metropolitan municipality were within city limits, up from 89% in 2007 and 61% in 1980. 64.9 % of the residents live on 35.1 % on the Asian side. While the city ranks as the world's 5th-largest city proper, it drops to the 24th place as an urban area and to the 18th place as a metro area because the city limits are equivalent to the agglomeration.

Today, it forms one of the largest urban agglomerations in Europe, alongside Moscow. The city's annual population growth of 3.45 percent ranks as the highest among the seventy-eight largest metropolises in the Organisation for Economic Co-operation and Development. The high population growth mirrors an urbanization trend across the country, as the second and third fastest-growing OECD metropolises are the Turkish cities of İzmir and Ankara. Istanbul experienced rapid growth during the second half of the 20th century, with its population increasing tenfold between 1950 and 2000; this growth in population comes, in part, from an expansion of city limits—particularly between 1980 and 1985, when the number of Istanbulites nearly doubled. The remarkable growth was, still is fueled by migrants from eastern Turkey seeking employment and improved living conditions; the number of residents of Istanbul originating from seven northern and eastern provinces is greater than the populations of their entire respective provinces.

Istanbul's foreign population, by comparison, is small, 42,228 residents in 2007. Only 28 percent of the city's residents are from Istanbul; the most densely populated areas tend to lie to the northwest and southwest of the city center, on the European side. Istanbul has been a cosmopolitan city throughout much of its history, but it has become more homogenized since the end of the Ottoman Empire; the vast majority of people across Turkey, in Istanbul, are Muslim, more members of the Sunni branch of Islam. Most Sunni Turks follow the Hanafi school of Islamic thought, while Sunni Kurds tend to follow the Shafi'i school; the largest non-Sunni Muslim group, accounting 10-20% of Turkey's population, are the Alevis. Mystic movements, like Sufism, were banned after the establishment of the Turkish Republic, but they still boast numerous followers. Istanbul is a migrant city. Since the 1950s, Istanbul's population has increased from 1 million to about 10 million residents. 200,000 new immigrants, many of them from Turkey's own villages, continue to arrive each year.

As a result, the city constant change reshaped to achieve the needs of these new population. The Patriarch of Constantinople has been designated Ecumenical Patriarch since the sixth century, has come to be regarded as the leader of the world's 300 million Orthodox Christians. Since 1601, the Patriarchate has been based in Istanbul's Church of St. George. Into the 19th century, the Christians of Istanbul tended to be either Greek Orthodox, members of the Armenian Apostolic Church or Catholic Levantines. In the late Ottoman period non-Muslim ethnic minorities in the empire used French as a lingua franca and therefore used French-language newspapers and other media. In addition French businesspeople and vocational workers used French-language media to get in touch with clients in the empire. French-language journalism was centred in Smyrna but by the 1860s it began shifting towards Constantinople. Many newspapers in non-Muslim minority and foreign languages were produced in Galata, with production in daylight hours and distribution at nighttime.

The Arabic newspaper Al-Jawāʾib began in Ottoman Constantinople, established by Fāris al-Shidyāq a.k.a. Ahmed Faris Efendi, after 1860, it published Ottoman laws in Arabic, including the Ottoman Constitution of 1876. There are today between 50,000 and 90,000 Armenians in Istanbul, down from about 164,000 according to the Ottoman Census of 1913. Bulgarian newspapers in the late Ottoman period published in Constantinople were Makedoniya, Napredŭk or Napredǎk, Turtsiya. There was a group of prominent ethnic Greeks and/or people adopting Greek culture, the Phanariotes, based in the neighbourhood of Phanar, now Fener, in Fatih. About eleven families were a part of the Phanariotes; because of events during the 20th century—including the Greek genocide, the 1923 population exchange between Greece and Turkey, a 1942 wealth tax, the 1955 Istanbul riots—the Greek population centered in Fener and Samatya, has decreased substantially. At the start of the 21st century, Istanbul's Greek population numbe

Nilamani Routray was an Indian politician and the Chief Minister of Odisha from 1977 to 1980. He served as the Health and Family Welfare Minister and Forest and Environment Minister in the Union Government led by V. P. Singh, he died on 4 October 2004. Nilamani Routray was a founder of the Odisha unit of All India Students Federation, he was the president of the Odisha state unit of the Indian National Congress from 1967 to 1970. He joined the Utkal Congress and became its president. Subsequently, he became the president of its state unit, he was elected to the Lok Sabha in 1989. His autobiography Smruti O Anubhuti won the Odisha Sahitya Academy awards in 1988