The Nuremberg Laws identified a Jew as someone who

The Nuremburg Laws identified a Jew by their race NOT by their religion*
They made them sow stars on their jackets so that people would know when you walk by that you were a Jew:/
So life was not very good to be a Jew if you were living during Hitler's times.
Hitler convinced everyone that Jews were the enemies, sadly millions of Jews were murdered...
hope this information benefits you.
:P