What impact did europe have after being invaded by many groups between 400 and 1000 AD?

Between 800 and 1000, three groups—the Magyars, the Vikings, and

Muslims—invaded Europe. The Magyars, fierce warriors from the east,

crossed over land and attacked Europe from Asia. Perhaps the most

frightening invaders of all, the Vikings, came from Scandinavia in the

north. The fierce Vikings used ships to travel along Europe’s coast

and up its rivers, looting towns and taking prisoners to sell as slaves.

The Muslims had already controlled Spain and attacked France, but

also crossed the Mediterranean Sea to invade southern France and

northern Italy

the answer to fill in the blank in this question would be the word resource, it is defined as the money, material or people (since human resource is a very valuable good) that a company or a person has at disposition (meaning they can use the resource as they see fit), to be able to complete a task or achieve a goal.