The Reichskreditkasse (RKK) was founded in 1939 in Occupied Poland as a central bank for the General Government. From May 1940 RKKs were established in all other occupied territories.

The RKK regulated payment and credit transactions for the German troops and administrative authorities.

Source:

https://portal.ehri-project.eu/units/de-002429-r_29. Accessed 20 June 2021.