The idea behind European banking supervision  About a year later, on 4 November 2014, the first pillar of a European banking union was erected. On that date, the ECB assumed responsibility for supervising the 120 largest banks in the euro area – with the accession of Lithuania, the number of supervised banks has risen to 123.
They needed to make sure that their economies did not return to the high and volatile inflation seen in previous decades. Further, they were looking for a way to keep inflation expectations under control. In general, central banks did a good job with this. Certainly the Bank of France was successful in the early 1990s in building credibility as an inflation-fighting central bank.