The Church of the East ( ʿĒ(d)tāʾ d-Maḏn(ə)ḥāʾ), also known as the Nestorian Church, is a Christian church within the Syriac tradition of Eastern Christianity. It was the Christian church of the Sasanian Empire, and quickly spread widely through Asia. Between the 9th and 14th centuries it represented the world's largest Christian church in terms of geographical extent, with dioceses stretching from the Mediterranean Sea to China and India. Several modern churches claim continuity with the historical Church of the East.