middle age 1

I want know about middle age in Europe.  I was interesting about Knight and Noble.  I want know how the Knight fight is them like be Individual heroism or be use Conspiracy.  Is the Noble can decide other people's life.  Is all the Noble are bad because in today's story and movie most Noble are bad.  They caught slave, kill, mine to people...  And is the Knight was justice?  There is lot thing I want know.  Also I want know how they live, what they eat normal why the Knight allegiance to Noble.  When they have different thinking what they do.