Forum of Theodosius

The Forum of Theodosius (Greek: φόρος Θεοδοσίου, today Beyazıt Square) was an area in Constantinople. It was originally built by Constantine I and named the Forum Tauri ("Forum of the Bull"). In 393, however, it was renamed after Emperor Theodosius I, who rebuilt it after the model of Trajan's Forum in Rome, surrounded by civic buildings such as churches and baths and decorated with porticoes as well as a triumphal column at its center.

In the middle of the forum was a Roman triumphal column erected in honour of emperor Theodosius I. Its shaft was carved with reliefs depicting this emperor's victory over the barbarians and a statue of him stood on top. An internal spiral staircase allowed visitors to reach the top of the column, where a stylite lived towards the end of the mid-Byzantine period. The statue of Theodosius collapsed during the earthquake of 478 although the column remained standing. It had no statue until 506 when a new statue of Anastasius I Dicorus was erected instead. Emperor Alexios V was sentenced to death in 1204 and thrown from the column. The column remained standing until the end of the 15th century, and some pieces of it were re-used in the construction of the Bath of Patrona Halil.

Excavations for the foundation trenches of the Faculty of Letters and Sciences of Istanbul University uncovered the remains of three basilicas. Their identities and names are unknown, and so they are called Basilicas "A", "B", and "C".

Basilica A is the only Justinianian-era (527-565) basilica whose plan is known. It has several distinct characteristics. Its central space was nearly a square, with two side courtyards. The narthex on the west side connects with the courtyards. The intervals between the columns separating the basilica's naves are closed off by balustrade slabs. The capitals resemble those at Hagia Sophia, also built by Justinian. The large pulpit (ambo) found in Basilica A is the only surviving ambo from the early Byzantine period and is kept in the garden of the Hagia Sophia.

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