Freiburger FC

Germany is a large country and the National Championships were organised on a regional basis, with three tiers of competition culminating in the national finals.
The regional competitions predate the national championships. For example, the  süddeutschen (Southern Germany) championship was first decided in 1898.
Frieburger FC were champions in 1898 and 1907. In 1907 they went onto become National Champions.