The Archbasilica of St John Lateran has been known by many names through its long history, the Basilica Aurea, the Basilica Constantiniana, the Archibasilica Sanctissimi Salvatoris et Sanctorum Iohannes Baptista et Evangelista in Laterano.This chapter outlines the vital role the world's first cathedral has played throughout history.From its earliest days the Basilica was central to the development of the Church.A summary history would note the synod of 313, convened at the so-called Domus Faustae to condemn Donatism even before the Basilicaߣs completion; synods of 649 against Monothelitism and 769 against Iconoclasm, and five ecumenical councils, each of profound importance, between 1123 and 1512.Intertwined with authoritative statements on Church governance from the palace and Patriarchum next to it, came a steady stream of teachings on proper form and liturgical practice as articulated within its walls.The chapter ends with the Holy Year of 1600.A visitor to the Lateran prior to the building projects that culminated then would have still been able to see many traces of Constantineߣs Basilica; key elements of the spolia that characterised its variegated interior still occupied the positions where their fourth-century builders had placed them.