What was the paper money that nobody trusted?

That's happened many times in history when the issuing government had little or no backing for its currency, resulting in inflation and general distrust.

In post-revolutionary America, early "Continental currency" was so poorly supported by the fledgling federal government that the expression "not worth a Continental" was used to describe something that was essentially worthless.

In the early 20th century the Weimar Republic in Germany was bankrupt and created runaway inflation by printing more and more bills with ever-higher denominations. At one point the exchange rate reached about one quadrillion (1015) marks to the US dollar.

More recently Zimbabwe's corrupt government issued bills with similarly high values and almost no purchasing power.