foederati

...The Western Empire during the Theodosian period was characterized by successive invasions by Germanic tribes and their founding within the empire, the reduction of the direct territory of the imperial government, and the drying up of tax revenues. During this time, the western government was no longer able to maintain its own military forces and was forced to fight other Germanic invaders with the help of Germanic allied tribes (foederati). The first wave of invasions was that of the Visigoths, who, taking advantage of internal conflicts within Rome due to the discord between Honorius and Stilicho and the execution of the latter (408), occupied the city of Rome under King Alaric in 410 and plundered it for three days...

*Some of the terminology explanations that mention "foederati" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…このテオドシウス朝期の西の帝国は相次ぐゲルマン諸族の侵入と帝国領内での建国，帝国政府の直接統治領の縮小，そして税収の枯渇によって特徴づけられる。　この間に西の政府は自らの固有の軍隊をもてなくなり，ゲルマン人の同盟部族(フォエデラティfoederati)の力で他の侵入ゲルマン人と戦うほかはなくなっていく。侵入の最初の波は4世紀の末から始まる西ゴートのそれで，ホノリウスとスティリコの不和，後者の処刑(408)というローマ側の内紛に乗じて，410年アラリック王の下，ローマ市を占領し3日にわたって劫掠した。…

※「foederati」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報