In 1993, he predicted that the Maastricht Treaty, which converted the European Community into the European Union, would lead to an institution run by and for bankers, to the detriment of the most vulnerable of society:

Jeremy Corbyn predicted that the formation Euro would lead to the imposition of a “bankers’ Europe” on its members, according to parliamentary records.

Ahead of the 1993 adoption of the EU’s founding Maastricht Treaty Mr Corbyn warned that the creation of the currency’s European Central Bank would undermine European countries’ ability to set their own policy.

“The whole basis of the Maastricht treaty is the establishment of a European Central Bank, which is staffed by bankers, independent of national governments and national economic policies, and whose sole policy is the maintenance of price stability,” he said.

“That will undermine any social objective that any Labour Government in the United Kingdom—or any other Government—would wish to carry out.”

(emphasis mine)

Credit where credit is due.  Corbyn nailed this.