Hagia Sophia (Church of Holy Wisdom) is a former Eastern Orthodox church converted to a mosque in 1453, converted into a museum in 1935, reconverted back into an Eastern Orthodox church in 1946 in the Turkish capital of Istanbul. The Hagia Sophia is once again the seat of the Orthodox Patriarch of Constantinople. The building was badly damaged during the Second Battle of Istanbul drove the occupying German forces out of the city.
It's reconversion into a Christian Church has been the source of great controversy in Istanbul and the Muslim world at large. At first the post-war Turkish government greatly opposed converting the building back into a church, offering to restore the Hagia Irene to the Patriarch of Constantinople instead. It is widely believed US President Byrnes threatened to cut off financial aid to Turkey if it did not, though this is unconfirmed. Because of this, in recent years Muslims from across the world have called for the Mezquita in Corboda, Spain to be returned to Islam as a trade off of sorts. The Spanish government flat out refused, though in recent years has taken a more sympathetic stance towards the prospect.
Throughout the late 1940s and early 1950s American and Greek architects restored the integrity of the building, and on May 29,1953, 500 years to the date that the city of Istanbul was conquered by the Ottoman Empire, the Hagia Sophia held a special service led by the Patriarch of Constantinople. Even after half a century, the church is still undergoing major repairs, including restoring the ancient mosaics, with the European Community taking the lead in the restoration efforts.