Fritz is a common German and Ashkenazi Jewish male name. The name originated as a German diminutive of Friedrich or Frederick (Der Alte Fritz, and Stary Fryc were common nicknames for King Frederick II of Prussia and Frederick III, German Emperor), as well as of similar names including Fridolin and, less commonly, Francis. Fritz (Fryc) was also a name given to German troops by the Entente powers equivalent to the derogative Tommy. Other common bases for which the name Fritz was used include the surnames Fritsche, Fritzsche, Fritsch, Frisch(e) and Frycz.
https://en.wikipedia.org/wiki/Fritz