Feudalism in the Middle Ages originated from what is now known as Germany. About 1,500 years ago, in the year 410 A.D., the Roman Empire fell apart in Europe, and it's land was divided. The legions had been pulling out of the northern frontiers such as Britannia (England) and Germania for some time, and the last straw came when the Visigoths, a barbarian tribe out of the north lands, sacked the city. This left the continent in a state of shock for many years. The overarching and powerful empire that had dominated the land for centuries was suddenly gone. People were left to fend for themselves, and in this time, many powerful Germanic clan leaders took this opportunity to make a name for himself. In Germanic clans for centuries, a primitive form of Feudalism had existed. The clan leader owned all of the land in the clan's area, and the men who fought for him were given land in return to farm and raise their families. Of course, as the empire fell, these clans became kingdoms, ruled in turn by kings. As their lands grew, so did this system. The kings still owned the land, and upon death of the king or the man the land was given to, it would be returned to the current king. Over time, a new form had developed in Germany, where the vassal enfeoffed the land, and became permanently bound to it and his family. When the vassal would die, his descendant would have to perform a new ceremony, called Lehnseid (An Act of Homage), to keep the land in his family's possession.
In turn, these vassals would enhoeff the land to other men, who would then pay homage to him as well. In return for this, the king could demand loyalty and an alliance from the vassal and his sub-vassals. So when the king went off to war, he would call upon all his vassals and their sub-vassals and he would have his army, as there were very small standing armies in that time. The system worked so well for the kings and his people since he could not demand monetary tribute from his subjects, as money was scarce, but land was plentiful and always in supply.