The Friedrichs family were long established in Schleswig-Holstein, and Kurt was born in its capital Kiel. However the family moved when he was very young and by the time he reached school age they had settled in Dusseldorf. Kurt's father became friendly with a fellow lawyer in Dusseldorf who was the brother of Felix Klein .
Ang Friedrichs pamilya ay matagal na naitatag sa Schleswig-Holstein, at Kurt ay ipinanganak sa kabisera nito Kiel. Subalit ang pamilya inilipat kapag siya ay napakabata at sa pamamagitan ng oras siya umabot sa paaralan edad nila ay husay sa Dusseldorf. Kurt's ama ay naging friendly sa isang tao abogado sa Dusseldorf na ay ang kapatid na lalaki ng Felix Klein.