By the end of the war, Europe owed other countries more than $10 billion. To offset this debt, countries began printing more money, which ultimately led to inflation. Middle class Europeans, who were relatively free of money worries before the war, began struggling just to make ends meet after the war.
World war 1
The depression is when the U.S. had very little or close to no money which then caused euroupeans to have very little money too after that may people in europe were unemployed homeless or went broke
In 1921 Luxembourg, a former member of the Zollverein, signed the Convention of Brussels with Belgium, creating the Belgium–Luxembourg Economic Union. Belgium and Luxembourg thereby had the same customs tarif and a single balance of payments since 1921.
One effect was the weakening of the economy of the Soviet Union which led to its eventual collapse
Some small European countries they combined their resources to have greater power for their econimics