Did feudalism evolve in response to invasions by vikings Muslims and Magyars?

The answerer hinges on the term evolve - whether it is meant as the driving force for the establishment of feudalism or the changes that the presence of external enemies required feudalism to change into a monarch .Feudalism initially provided structure when larger social structures disappeared and local, non-centralized, authority was required.. As an example when the Roman Empire pulled out of Britain. The system allowed the development of an economy with workers and leaders with a strong defensive capacity for both external and internal (policing activities.Under the pressures of competition between competing feudal outposts and the need for unified battle strategies the feudal system eventually gave way to monarchies.