Asignificant cause of the great depression of the 1930’s was that

Bank Failures

Explanation:Bank deposits were uninsured and while banks kept failing people they lost their savings.The Surviving banks were unsure what to do and in an effort to keep the bank going they stopped creating knew loans.That only worsened the situation leading to less and less expenditures.

i would say it is the roman empire europe after the norman conquest.