The Bank Run happened right after the Stock Market Crash of 1929. Due to this crash, many individuals were not able to pay back banks for the loans they took out. This lack of currency caused a panic, resulting in banks running out of currency.
This leads to the Bank Runs of the 1930's. This was when individuals rushed to their respective banks in order to take out their savings. This was a time were banks were not protected by the FDIC and their savings were not secure.
This economic instability lead to international conflicts for the US, as their trading partners were worried about how this failure would affect their transactions with the US.