Which empire built the Hagia Sophia’s original sixth-century structure in Constantinople?

The Byzantine Empire built Hagia Sophia’s original sixth-century structure in Constantinople under Emperor Justinian I.

The present building was completed in 537 after earlier churches on the site were destroyed during political unrest. Architects Anthemius of Tralles and Isidore of Miletus designed its vast dome and innovative supporting system. For centuries, Hagia Sophia served as the principal cathedral of Constantinople and a major centre of Eastern Christian worship.

The Ottoman conquest of Constantinople in 1453 transformed it into a mosque, and architects added features including minarets over later periods. It became a museum in 1935 and was converted back into a mosque in 2020. The building’s layered history reflects Byzantine, Ottoman and modern Turkish cultural heritage.