Apple crumble, also known as apple crisp, is a modified version of apple pie. As we know that apple pie is originally from England, and so is apple crumble. In the Second World War, there were shortages of pastry ingredients. Dealing with this kind of situation, the people there tried to lower the use of flour, fat and sugar which are used a lot in making pie pastry. Reducing those pastry’s main ingredients and adding oatmeal to make crumble mix was an economical alternative. Since then, apple crumble became popular.