Hitler came to power legally in January 1933, promising to remove Jewish influence from German life. In April 1933, Germans burned Jewish books and forced most Jewish government employees and professionals to leave their jobs. Jewish life was further restricted by September 1935 by the passage of the Nuremburg Laws. These laws identified Jews by the religion of their grandparents. Some people who practiced Christianity discovered they were now classified as Jews who lost all rights of citizenship. Hitler also decided to “improve the purity of the Aryan race” by killing all German adults and children who had physical or mental disabilities. After 1937 Jewish children were not allowed to go to school, swim in public pools or even play on public playgrounds. Germans forced Jews out of their businesses and required them to wear a yellow star for identification. As things got worse, many left Germany but others stayed behind hoping things would get better. Some who wanted to leave could not obtain entry into other countries. The Nazis found an excuse to organize large scale violence against the Jewish people. When a Jewish teenager shot a German diplomat in Paris, German authorities immediately instigated mob violence on November 9 and 10, 1938. Thousands of Jewish businesses were destroyed and synagogues burned. So many store windows were smashed and homes ransacked that this night became known as Kristallnacht or Night of Broken Glass. Many Jews were beaten and at least 91 killed, and authorities sent over 30,000 Jewish men between the ages of 16 and 60 to concentration camps. After Germany invaded Poland in 1939, they forced Polish Jews out of their homes and into closed-off neighborhoods called ghettos. Many families had to leave everything behind. They could only bring what they could carry. Food was scarce and the ghettos were very crowded. In many ghettos, the Germans forced the Jews to work making supplies and munitions for the German army. Many Jews were worked to death. Others died of starvation or were shot trying to escape. Jews were rounded up and sent to death camps regularly.