In the Middle Ages was Tilithigau, approximately located between Bad Pyrmont and Hameln, the most densely populated district in Germany. Around the year 1250 the Bishop of Minden from the Diocese of Fulda acquired parts of the Weser mountain country for 200 pounds of silver, and settled people from the Tilithigau there. The one called the Tilly, ie from the Tilithigau. The name Tilithi "people" or "people" means. The general TILLY from the 30 Years War (1618-48) has nothing to do with the German name. He was named after a county in what is now Belgium. The name TILLY is therefore a urwestfälischer name.