How did Hamburg, known as one of the five western fast food, originate?

The original hamburger was a meat pie made of ground beef and flour, so it was called beef patties. In ancient times, Tatars had the habit of eating beef raw. As the Tatars moved westward, they were introduced to the Balkans and then to Germany, gradually turning raw food into cooked food. People in Hamburg, Germany, improved it by kneading chopped beef sauce in flour, spreading it into cakes, frying it and eating it, so they named it "hamburger patties" after the name of the place. From 65438 to 0850, German immigrants brought the cooking technology of hamburger patties to the United States. Later, it was renovated and gradually integrated with sandwiches, and the beef patties were sandwiched in buns cut in half, which were called "hamburgers".