c. 1300, popular name of the cathedral church of St. John Lateran at Rome, which is built on the site of the palace of the Plautii Laterani, a Roman family. Given by Constantine to the bishop of Rome, as a papal headquarters and residence for nearly 1,000 years it was the site of five general councils of the Western Church, that of 1215 being regarded as most important. The Lateran Accords of 1929 settled the relationship between Italy and the Holy See.