4. Brothers Grimm at first studied to become lawyers, like their father. Under above mentioned circumstances and inspired from one of their professors they begun exploring cultural inheritance of not fully integrated Germany. Most countries in Europe in 18th century still didn't develop national awareness and Germany was no exception.
The invisible glue with great potential of connecting different people with different dialects, different backgrounds and different interests under one state, were legends and fairy tales. People from East, West, South and North parts of Germany barely shared their language but they certainly shared numerous folk stories. Only few of them were written and young brothers started to collect them.
5. Legends and fairy tales were not the only occupation of Jakob and Wilhelm who soon became respected researchers of cultural past of German culture. They also started writing first dictionary of German language. Of course this was tremendous job and none of them never saw the final result: complete dictionary with impressive weight of more than 80 (!) kilograms.
6. First edition of Children and Household Tales with 86 stories in first volume and 70 stories in second volume was meant for scientists and researchers only. Soon they realized the potential of the stories loaded with morals. It seemed just right to present them to children in new society. Old feudal system was retreating to new order of bourgeois society. With fairy tales children could easier understand what is right and what is wrong.
Of course brothers Grimm had their own system of values developed on reformed Calvinistic doctrine. They believed in hard work and modest life, so they favored stories which featured perseverance, honesty and fairness. Some fairy tales already fitted in this model, others have been rewritten.