Timothy W. Guinnane, an #economics professor at Yale, has published a lot of interesting research about the history of the German #cooperative movement.

This paper describes how early credit cooperatives in 1889-1914 were able to thrive, even if "few if any locals had any banking experience, and most were not even familiar with basic accounting methods". The paper also describes the role of the early cooperative auditing associations.

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=275185