Government was based around Feudal Law.
This was a system whereby a man was given something and in return he served a master.
An example of this: A peasant or worker given land and in return he served his master by working on his land. He became a vassal of that master.
The king ruled over the country, but individual barons and lords formed the true government.
Barons were vassals to the king.
Lords were vassals to barons.
Peasants or workers were vassals to lords.
A lord managed his own estate (Manor) and he owned everything on it including the workers. The manor consisted of the castle or manor house, the land, church, farms and from this a village or town would develop.
A lord had absolute power over his manor. He would levy taxes, produce his own money and preside over justice. The Lord would keep his workers (vassals) safe and in return he expected hard work and loyalty.
If the king needed to raise an army he would do so through his barons and lords. They were responsible for supplying the soldiers to the king.
A vassal must serve his master, pay him taxes and go to battle when required.