Explain feudalism for social studies

Feudalism, also known as the feudal system, was the combination of the legal, economic, military, and cultural customs that flourished in Medieval Europe between the 9th and 15th centuries.

the dominant social system in medieval Europe, in which the nobility held lands from the Crown in exchange for military service, and vassals were in turn tenants of the nobles, while the peasants (villeins or serfs) were obliged to live on their lord's land and give him homage, labor, and a share of the produce, notionally in exchange for military protection.

Explanation:

john maynrd keynes developed new economic respose to the                           ( b. great depression if the 1930's)