After the fall of the Roman Empire, the feudal system developed in much of Europe. In this system, monarchs often granted land to important nobles in return for their military support. In other cases, powerful landholding nobles were persuaded through diplomacy to form alliances and give support to a central monarch. The nobles promised to provide the monarch with soldiers and supplies in times of war, as well as support through taxes. They often subdivided their lands to lesser nobles or knights. Most of the common people were serfs — peasants were the property of their lords and worked the land for them. They were allowed to have their own houses but could not move to any other place. They had to give part of their crops and other products to the nobles who, in turn, sent much of it to the king and queen. The serfs also served as soldiers in time of war. In return, the nobles offered them protection from invaders