The holocaust happened because there were many different invasions in different areas in Europe, then the Jews that were living in those areas were prosecuted. An example is the invasion of Poland, before 1939 there was little to no Jews prosecuted from Poland. All of a sudden after the Germans invaded Poland, you can see many People from Poland being prosecuted.
Group, location, and events impacted a persons experience because after 1939 there were so many more people being prosecuted that the camps would have started to become more crowded and there was probably more people killed in them to control the amount of people in them. Group could impact a persons experience because if they are grouped with more elderly and sick people, instead of healthy and Young people that can work, they might be more likely to be killed because they can’t work so the Germans wouldn’t see the point in having them live.