Answer and Explanation:
Feudalism is a political, economic and social system that developed in Europe during the Middle Ages. It started after the collapse of the Roman Empire and we can actually said that one of the main reasons for its introduction was the fall of that Empire. It was a system based on loyalty, where rulers were giving their land to vassals, who were using the land and paying taxes. Peasants were doing all the hard work.
On the other side, Feudalism started declining with the emergence of new ideas, creation of a new social layer - merchants, craftsman... and especially with the Renaissance movement. It is interesting that in France feudalism lasted until 1789, when during the Revolution old regime was overthrown.