The Church of the Holy Saviour in Chora (Greek: Ἐκκλησία τοῦ Ἁγίου Σωτῆρος ἐν τῇ Χώρᾳ, Turkish: Kariye Müzesi, Kariye Camii, Kariye Kilisesi) is a medieval Byzantine Greek Orthodox church preserved as the Chora Museum in the Edirnekapı neighborhood of Istanbul. The neighborhood is situated in the western part of the municipality (belediye) of the Fatih district. In the 16th century, during the Ottoman era, the church was converted into a mosque; it became a museum in 1948. The interior of the building is covered with some of the oldest and finest surviving Byzantine mosaics and frescoes; they were uncovered and restored after the building was secularized and turned into a museum.
The Chora Church was originally built as part of a monastery complex outside the walls of Constantinople, to the south of the Golden Horn. The church's name means The Church of the Holy Redeemer in the Fields. (Greek: ἡ Ἐκκλησία τοῦ Ἁγίου Σωτῆρος ἐν τῇ Χώρᾳ, hē Ekklēsia tou Hagiou Sōtēros en tēi Chōrai). The last part of that name, Chora, referring to its location originally outside of the walls, became the shortened name of the church. The original church on this site was built in the early 4th century, and stood outside of the 4th century walls of Constantine the Great. However, when Theodosius II built his formidable land walls in 413-414, the church was within the city's defences, but retained the name Chora.
The majority of the fabric of the current building dates from 1077-1081, when Maria Dukaina, the mother-in-law of Alexius I Comnenus, rebuilt the Chora Church as an inscribed cross or quincunx: a popular architectural style of the time. Early in the 12th century, the church suffered a partial collapse, perhaps due to an earthquake. The church was rebuilt by Isaac Comnenus, Alexius's third son. However, it was only after the third phase of building, two centuries after, that the church as it stands today was completed. The powerful Byzantine statesman Theodore Metochites endowed the church with many of its fine mosaics and frescos. Theodore's impressive decoration of the interior was carried out between 1315 and 1321. The mosaic-work is the finest example of the Palaeologian Renaissance.