Assuming this is the social hierarchy of the feudal system in the Middle Ages in Europe , the lowest would be the Serfs they were the ones that took care of the land of the knights and provided them food followed by the Merchants and Artisans, then were the Knights who worked for land in exchange of their loyalty and bravery to the next class in charge the Nobles, and at the top of the hierarchy was the Monarch or King and the Clergy who were the ones that ruled of all the land as they were also the ones who made the laws.
1) Monarch and Clergy
2)Nobles
3)Knights
4)Merchants and Artisans
5)Serfs