Anthemius of Tralles (Ancient Greek: Ἀνθέμιος ὁ Τραλλιανός, Medieval Greek: [anˈθemios o traliaˈnos], Anthémios o Trallianós; c. 474 – 533 x 558) was a Byzantine Greek from Tralles who worked as a geometer and architect in Constantinople, the capital of the Byzantine Empire. With Isidore of Miletus, he designed the Hagia Sophia for Justinian I.
Isidore of Miletus (Greek: Ἰσίδωρος ὁ Μιλήσιος; Medieval Greek pronunciation: [iˈsiðoros o miˈlisios]; Latin: Isidorus Miletus) was one of the two main Byzantine Greek mathematician, physicist and architects (Anthemius of Tralles was the other) that Emperor Justinian I commissioned to design the cathedral Hagia Sophia in Constantinople from 532 to 537. He was born c. 475 AD. The creation of an important compilation of Archimedes' works has been attributed to him. The spurious Book XV from Euclid's Elements has been partly attributed to Isidore of Miletus.
Hagia Sophia, officially the Hagia Sophia Grand Mosque, is a mosque serving as a major cultural and historical site in Istanbul, Turkey. It was formerly a church (360–1453) and a museum (1935–2020). The last of three church buildings to be successively erected on the site by the Eastern Roman Empire, it was completed in AD 537, becoming the world's largest interior space and among the first to employ a fully pendentive dome. It is considered the epitome of Byzantine architecture and is said to have "changed the history of architecture". From its dedication in 360 until 1453 Hagia Sophia served as the cathedral of Constantinople in the Byzantine liturgical tradition, except for the period 1204–1261 when the Latin Crusaders installed their own hierarchy. After the fall of Constantinople in 1453, it served as a mosque, having its minarets added soon after. The site became a museum in 1935, and was redesignated as a mosque in 2020.
The current structure was built by the Byzantine emperor Justinian I as the Christian cathedral of Constantinople between 532–537 and was designed by the Greek geometers Isidore of Miletus and Anthemius of Tralles. It was formally called the Temple of God's Holy Wisdom, (Greek: Ναὸς τῆς Ἁγίας τοῦ Θεοῦ Σοφίας, romanized: Naòs tês Hagías toû Theoû Sophías) the third church of the same name to occupy the site, as the prior one had been destroyed in the Nika riots. As the episcopal see of the ecumenical patriarch of Constantinople, it remained the world's largest cathedral for nearly a thousand years, until the Seville Cathedral was completed in 1520.