Answer:
Step-by-step explanation:
Cause: The threat of invasion by barbarians and huns.
Effect: The need for defense and fortification of borders and territories, as well as the development of military strategies and tactics to protect against attacks. This led to the establishment of strong armies and the construction of defensive structures, such as walls and fortresses, in various regions.
Weak and corrupt political leaders
Cause: The leadership of individuals who were unable or unwilling to effectively govern and manage their territories and populations, often due to factors such as incompetence, corruption, or lack of legitimacy.
Effect: The erosion of social and political stability, as well as the weakening of institutions and systems that were designed to provide security, justice, and prosperity. This often resulted in social unrest, economic decline, and political instability, which could further exacerbate the vulnerability of a society to external threats and internal conflicts.