A region is a part of a country.
Some federalists speak of a “Europe of the Regions”. Talk of a “Europe of the Regions” partly reflects the desire to reduce the powers and functions of nation states by shifting governmental powers.
Powers would be transferred upwards to the supra-national EU level and downwards to sub-regions within each national territory, or even to natural geographical or historical regions which do not match present nation-state borders. Such a Europe would bear some similarity to the Europe of many political units that existed in former times.