1999   Poland, Hungary, and the Czech Republic join the North Atlantic Treaty Organization (NATO).

2003   The Letter of the Eight is signed by leaders of eight countries including the United Kingdom, Spain, Italy, Portugal, Denmark, Poland, Hungary and the Czech Republic, demonstrating support for the United States' plans to invade Iraq.

2004   Ten nations are added to the European Union including Poland, Lithuania, Latvia, Estonia, the Czech Republic, Slovakia, Slovenia, Hungary, Malta and Cyprus. The expansion is the largest expansion to date.