Hagia Irene, also known as Saint Irene, is a historical Eastern Orthodox church located in Istanbul. It holds the distinction of being the oldest known church in the city and is the only Byzantine church in Istanbul that has never been converted into a mosque. Instead, it served as an arsenal for storing weapons until the 19th century. Today, Hagia Irene functions as a museum and concert hall.
The church was initially dedicated to the peace of God and was one of the three shrines that emperors devoted to different attributes of God, along with Hagia Sophia (Wisdom) and Hagia Dynamis.
According to tradition, the building was constructed on the site of a pre-Christian temple. It was the first church to be completed in Constantinople, even before Hagia Sophia, during the city's transformation into the eastern capital of the Roman Empire. Emperor Constantine I is said to have commissioned the first Hagia Irene church in the 4th century, which was completed before the end of his reign in 337. It served as the church of the Patriarchate until Hagia Sophia was finished in 360 during the reign of Constantius II. Unfortunately, during the Nika revolt in 532, Hagia Irene was burned down. However, Emperor Justinian I had the church rebuilt in 548. It suffered damages again due to the Constantinople earthquake of October 20, 740, shortly before the death of Leo III. Emperor Constantine V ordered its restoration, which included the decoration of its interior with mosaics and frescoes. Some of these restorations still exist today.
After the fall of Constantinople in 1453, the church was enclosed within the walls of the Topkapi Palace. It was subsequently used by the Janissaries as an arsenal until 1826. During this period, it functioned as a warehouse for military equipment and a repository for trophies of arms.
