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Who
Involved high-ranking lords, knights who provided protection, and serfs who did agricultural labor
What
An economic and political system used in Western Europe, where landowners gave a fief (piece of land) to a vassal in exchange for protection/service. Serfs were forced to labor the land. (basically each class served the one above it)
Where
Western Europe, typically within fragmented kingdoms/Germanic states
When
The middle ages, after the fall of the western roman empire. A time of fragmentation and competing states
Why
Helped bring a sense of stability to a declining western europe (for a short period of time). Shaped the economy/government of Europe (separate states/localized govs) Further encouraged inequalities.