Forum Romanum
Outlines of Roman History: Decline of the Empire: Disintegration of Empire
This article from Morey's 1901 textbook recounts the attacks on the Roman Empire by the Sassinids from the east and the Germanic barbarians from the north.
Forum Romanum
Outlines of Roman History: Decline of the Empire: The Illyrian Emperors
In this article from the 1901 textbook by William Morey, you can read that the Roman empire had a period of stability before its further decline.
World History Encyclopedia
World History Encyclopedia: Alemanni
Encyclopedia entry on Alemanni, a confederacy of Germanic-speaking peoples who occupied modern day Germany. Site has maps, links to further material and timeline of events.
Stephen Byrne
History for Kids: The Fall of the Roman Empire
Article ending with a short quiz for kids gives an overview of the weakening and eventual fall of the Roman Empire.