The euro is now the new currency for millions of Europeans. 11 September 2001 becomes synonymous with international terrorism after hijacked airliners are flown into buildings in New York and Washington. Countries begin to work much more closely together to fight crime. The split between Eastern and Western Europe is healed when 10 new countries join the EU in 2004, followed by Bulgaria and Romania in 2007. A financial crisis hits the global economy in September 2008. The Treaty of Lisbon provides modern institutions and more efficient working methods.
26 February 2001 – Treaty of Nice
EU leaders sign the Treaty of Nice. It aims to reform the institutions so the EU can function efficiently after reaching 25 member countries and prepare for the next major group of new members joining. It comes into force on 1 February 2003.
11 September 2001 – Terrorist attacks in the United States
Hijacked airliners are flown into the twin towers of the World Trade Center in New York and the Pentagon building in Washington. Nearly 3,000 people die. The EU countries stand firmly alongside the United States in the fight against international terror.
1 January 2002 – Euro notes and coins launch in 12 countries
Euro notes and coins become the legal currency in 12 EU countries (Greece joined the euro zone in 2001 and more follow after 2002). Printing, minting and distributing them is a major logistical operation. Notes are the same for all countries. Coins have one standard side, while the other carries a national emblem.
31 March 2003 – Peacekeeping operations in the Balkans
As part of its foreign and security policy, the EU takes on peacekeeping operations in the Balkans, firstly in the former Yugoslav Republic of Macedonia (now North Macedonia), and then in Bosnia and Herzegovina. In both cases, EU-led forces replace NATO units.
1 May 2004 – 10 new countries
Cyprus and Malta join the EU along with 8 Central and Eastern European countries — Czechia, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia and Slovenia — finally ending the division of Europe after the Second World War.
29 May-1 June 2005 – EU constitution
Voters in France and the Netherlands reject the Treaty establishing a constitution for Europe, which was signed by the 25 EU member states in October 2004.
1 January 2007 – The EU welcomes Bulgaria and Romania
Two more countries from Eastern Europe - Bulgaria and Romania - join the EU, bringing the number of Member States to 27.
13 December 2007 – Lisbon Treaty
The 27 EU countries sign the Treaty of Lisbon, which amends the previous treaties. It is designed to make the EU more democratic, efficient and transparent, and thereby able to tackle global challenges such as climate change, security and sustainable development. All EU countries ratify the Treaty before it enters into force on 1 December 2009.
September 2008 – Global economic crisis
A major financial crisis hits the world economy. The problems start with mortgage loans in the United States. Several European banks also experience difficulties. The crisis leads to closer economic cooperation between EU countries.