On 29 may, 1453, the plunder of Constantinople by the Turks led to the profanation of the St. Sophia, constructed between 532 and 537 AD by the Byzantine emperor Justinianus. The dome of St. Sophia was despoiled of the oblations of ages. The gold and the silver, the pearls and jewels, the vases and sacerdotal ornaments had been removed and the church was transformed into a mosque (The Spanish King transformed mosques into cathedrals around the same time).
The rich and portable of the Eastern faith had been removed, the crosses were thrown down and the walls, which were covered with images and mosaics, were washed and purified, and restored to a state of naked simplicity. On the ensuing Friday, 30 May 1453, the muezin proclaimed for the first time the ezan, or the public invitation for the prayer. The new name of the mosque was Haghia Sophia, which became a museum in 1934. Not all decoration of the faith of the conquered faith was removed for ever however. Experts have recently uncovered one of the four angel mosaics. The mosaic of an angel measures 1.5 meters by 1 meter and is believed to date from the 14th century. The discovery highlights the historical ties and common history of Turkey and Christian Europe. (Source: E. Gibbon, The Decline and Fall of the Roman Empire Volume VI (London 1994).