330 c.e., when it was renamed Constantinople.
The city remained the capital of the ensuing Byz-
antine Empire and the center of the Byzantine
Orthodox Church (now known as the Greek
Orthodox Church) for 1,000 years. One of the
most spectacular churches in the East, the Hagia
Sophia (or Aya Sofia) Basilica, was built there on
the site of an older church and dedicated by the
Byzantine emperor Justinian (r. 527–565) in 537.
Constantinople was on the route crusaders took
from Europe to syria and palestine between the
late 11th century and the 13th century, and it was
plundered and occupied by European soldiers
during the Fourth crUsade (1202–04). It became
the capital of the Latin Empire until 1261, when
the Byzantines recaptured it. The Fourth Crusade
has remained a bitter memory for many Orthodox
Christians and still affects their relations with the
Roman Catholic Church.
Attracted by Constantinople’s wealth, strategic
importance, and prestige as a center of culture
and learning, and inspired by a hadith calling on
Muslims to conquer the city, Arab armies besieged
Constantinople between 674 and 678 and again
in 717–718, but they were unable to take it. The
Byzantine Empire suffered substantial losses of
land in Anatolia and Thrace when Muslim Turkish
armies invaded beginning in the 11th century, and
the city was finally taken by the Ottomans under
Sultan Mehmed II (the Conqueror) in 1453. It was
then resettled with people from other parts of the
empire and developed as an Ottoman Muslim city
through the construction of mosqUes and Islamic
economic and social institutions. The Hagia Sophia
Basilica was converted into an Ottoman state
mosque. Nonetheless, the city was never exclusive
to Muslims; significant numbers of Christians and
Jews continued to live there. It remained the seat
of the Ottoman government until the dynasty was
overthrown by mUs taFa kemal atatUrk in 1922,
after which time Ankara was proclaimed capital
of the nascent Republic of Turkey. The Aya Sofia
Mosque was converted into a museum in 1935,
reflecting the strong secular outlook of the new
Turkish republic. While the city was referred to
by many different names through the Ottoman
period (Istanbul, Kostantiniye, Der Saadet, Islam-
bol), it was not until 1930 that it was officially
named Istanbul, the Turkish rendering of a Greek
phrase meaning “in the city.”
With 11.3 million residents (2007 estimate),
Istanbul remains the largest city in Turkey. It has
the largest port and is the commercial and cultural
center of the country. It is the fifth-largest city in
a Muslim-majority country, after cairo, Jakarta
(indonesia), Dakha (bangladesh), and Karachi
(pakistan). Like other major urban areas, it suffers
from air and water pollution and overcrowding due
to mass migrations from rural areas of the country.
Istanbul is also a major tourist destination. Roman
and Byzantine remains include the Hippodrome,
underground cisterns, and many churches, includ-
ing the Aya Sofia. Ottoman monuments include
many mosques, such as Süleymaniye and Sultan
Ahmed, palaces such as the Topkapi Palace, and
the Grand Bazaar.
See also cities; ottoman dynasty.
Mark SoileauThe magnificent Süleymaniye Mosque (16th century),
as seen from the Golden Horn, Istanbul, Turkey (Juan
E. Campo)
K 384 Istanbul