From a current-day perspective, the first EC capital rules were very simple and comprised credit risk only. Since then, European regulation of the financial sector has evolved considerably. Basel I was replaced by Basel II, which to a larger extent took modern risk management techniques into account.
Another wave of  Page 3 of 7  regulation followed in the wake of the financial crisis. This was based on the acknowledgement that one of the reasons for the depth of the financial crisis was that capital requirements had been eased too much under Basel II.