提 要：君士坦丁堡曾是地中海世界东部地区的重要城市，于君士坦丁一世时期奠基为帝国的首都。晚期罗马帝国时期的众敌环伺的危局以及君士坦丁堡所处的战略位置是君士坦丁一世在确定离开罗马、在东地中海建立新首都之时首要考虑的因素，而其选址标准在本质上根植于晚期罗马帝国防御体系重建的内在逻辑之中，君士坦丁一世的个人作用有其地位，但不是根本原因。君士坦丁堡落成之后，帝国各地资源倾注于此,与此同时，君士坦丁堡的政治地位也逐渐上升，并成为东部地中海世界的新中心。

关键词：君士坦丁堡；晚期罗马帝国；防御体系；地中海世界

Title: On the Relationship Between the Construction of Constantinople and the Reconstruction of the Defense System of the Later Roman Empire

Author:Dong Xiaojia, Assistant Professor, School of History, Culture & Tourism, Guangxi Normal University, Guilin, Guangxi, 541001, China.

Abstract: Constantinople was an important city in the east of the Mediterranean world and the capital of the Byzantine Empire, which was founded during the time of Constantine I. The dangerous situation of many enemies around it in the later Roman Empire and the strategic location of Constantinople was the main consideration of Constantinople. And in essence, the site selection criteria was rooted in the internal logic of the reconstruction of the defense system in the later Roman Empire. The personal role of Constantine I had its position, but not the primary cause. After the completion of Constantinople, the sources of all the empire were poured into Constantinople. At the same time, the political position of Constantinople was up gradually, and it became the new centre of the east Mediterranean world.

Key words:Constantinople; the Later Roman Empire; Defense System; the Mediterranean World