In our study we analyze the causes by which the mobility of the population or its relocation takes place, such as: economic crises, political instability, wars with the analysis of numerous literary sources that reflect these aspects, e.g.  Seneca, ad Hel. matrem, from consolatione 6.2, Livio ad urbe 39.3.6, 41.8.9, 25.1.8; Suetonius in Aug.42.3. Moreover, we examine in our study the migratory policies and the refugee crisis that Roman diplomacy had to leaded and that, in its evolution, forced the establishment of border controls in the Lower Empire, particularly in the city of Constantinople, which becomes, before a vertiginous demographic development, in zone of religious, economic and political reference as of 4 th Century; thus we will study many vicissitudes such as the scarcity of housing in which the locals give their homes to the foreign population as Procopio tells us, arc.23.24 and other aspects that are inferred from sources such as: Temistio, Or.3.48, Or. 18. 221a-223b, Zosimo 2.35 and Novels of Emperor Justinian Nov. 80, which also reflects a Christian stamp and a theocratic conception of the State to protect its legislation. These and other vicissitudes have a parallel that is reflected in the migratory crises that have occurred later and in our century.


Keywords: quaesitor; migration; borders; urban pólice.