in the March 1999 kicked Poland, Czech Republic and Hungary as the first Eastern European countries to join the western defense alliance.
2002 followed Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia.
2009 took NATO Albania and Croatia on, 2017 Montenegro. As the 30th member country followed 2020 North Macedonia.
As a further accession candidate applies Bosnia and Herzegovina. the Ukraine and Georgia future membership was offered at the 2008 NATO summit; however, the formal admission process has not yet begun.
Image source: colourbox.de