At the time the only concern was that member states should be prevented from violating human rights, hence the establishment of the European Convention on Human Rights in 1950 and the establishment of the European Court of Human Rights. The European Court of Justice recognised fundamental rights as general principle of European Union law as the need to ensure that European Union measures are compatible with the human rights enshrined in member states' constitution became ever more apparent.
What other entity was established at the same time as the European Convention on Human Rights?
European Court of Human Rights.