An imperial church is a church associated with an empire. The first such church was the state church of the Roman Empire, as patronized and largely controlled by the Roman Emperors from the time of the transfer of the seat of government to Constantinople. The link between the church within that empire and the state was formally established by Theodosius I with the Edict of Thessalonica of 27 February 380. The term imperial church has been used also with reference to a vision of the Church of England as the church of the British Empire.