Germany hyperinflation occurred from 1922-1923. What caused hyperinflation is that Germany had to pay reparations to the countries involved in the WWI conflict, specifically France. When Germany couldn't make the payments, France occupied the southern German coal fields. France would take the coal instead of German money. Germany responded by printing massive amounts of paper money in order to pay reparations. The problem with this was hyperinflation.
Small municipalities began to print notgelds between 1914-19 during WWI.
These notgelds replaced the mark because it became increasingly difficult to get marks from the Weimar Republic.
Germany had no gold or other assets to back the mark, Germany instead printed more marks that became worthless resulting in hyperinflation.
To combat hyperinflation, Germany created a new mark, the Rentenmark. The Rentenmark was backed by land and industrial assets instead of gold. After the Rentenmark, it was replaced with the Reichsmark. Germany took out loans to buy gold thereby backing the new mark, the Reichmark. This mark is what you see up to the end of WWII.
Below are examples of the Rentenmark and the notgeld.
The Rentenmark:
1937 Germany
2 Rentenmark
125x70mm
P-174b


The notgeld, Bad Kreuznach.
1917-18 Germany
50 pfennig
100x71mm
N-207917

