Indeed the Holocaust didn’t suddenly happen. It came after hundreds of years of antisemitism in Europe, whereby the Jews were constantly subjected to discrimination and pogroms. By the early 1900s many Jewish people had managed to become educated (despite the quotas and discrimination applied by the universities) and go on to work in professional fields, whilst others became successful businessmen. This was resented hugely by many people, despite the fact that in Eastern Europe many Jews remained very poor, and this resentment was used by the Nazis to justify the state initiated discrimination, starting in Germany in the early 1930s and continuing through until the end of WW2.
It isn’t hard to understand why the Jewish people wanted to return to their homeland, where some Jews had remained, despite every effort of surrounding tribes and invaders, for four thousand years. They fought to stay there with the already resident Jews, and some Arabs and Christians, and the state of Israel was born.