When the Turks breached the walls of Constantinople
on 29 May 1453, they extinguished the longest-lived political entity of Europe, the Byzantine state
. The disappearance of this ancient Christian polity from the living family of nations reduced its civilisation to a study for historians and archaeologist. Even the name of the state was quickly forgotten and scholars began calling it Byzantium,
which had been the original name of its capital city Constantinople. The "Byzantines"
themselves had called their state the "Roman Empire",
or in common parlance "Romaneia",
since it was in fact a continuation of the Roman empire in its fiscal, legal and administrative systems - even thought it had evolved into a Christian and primarily Greek-speeking state and the city of Rome itself had ceased to be part of the empire by ninth century. Thomas F. MathewsByzantium: From Antiquity to the Renaissance