Ireland takes over the six-month rotating presidency of the Council of the EU. Stability, jobs and growth are the Presidency’s three priorities.
The European Commission launches the European Year of Citizens, which will focus on the practical rights and advantages people gain from EU citizenship.
The Treaty on Stability, Coordination and Governance in the Economic and Monetary Union (popularly known as the 'fiscal compact') enters into force. It aims to strengthen fiscal discipline in the euro area through the 'balanced budget rule' and a correction mechanism.
Marseille (France) and Košice (Slovakia) are the European Capitals of Culture 2013. Both cities will host events to promote their local culture.
The Eurogroup appoints a new President – Dutch Minister of Finance Jeroen Dijsselbloem – for a two and a half year term.
Finance ministers agree in principle to 11 euro area countries introducing a financial transaction tax.
During a European Council meeting, the EU countries reach an agreement on the Multiannual Financial Framework 2013-2020. It sets out the limits and the principles of the EU's annual budget for these years.
A European Council is held in Brussels, mainly devoted to the economy.
As part of a package of proposals for a new, reformed EU fisheries policy, EU ministers reach informal agreement at the Council on protecting endangered stocks and ending 'discards' - the practice of throwing unwanted fish back into the sea.
The Council reaches political agreement on recommending a 'Youth Guarantee' scheme for the under 25-year olds. This will ensure that they are offered employment, training, further education or an apprenticeship within four months of leaving school or of becoming unemployed.
The phasing-out period for testing cosmetic products on animals ends, meaning that cosmetics tested on animals can no longer be marketed in the EU.
EU leaders endorse the Union's economic priorities for 2013 at the European Council and provide strategic guidance for the Member States' national budgetary policies and structural reforms for the year. This is part of the six-month policy coordination cycle known as the 'European Semester'.
The Eurogroup reaches a political agreement on the future economic adjustment programme for Cyprus. The aim is to restore the country’s public finances and financial sector.
Serbia and Kosovo sign a pact in Brussels, after negotiations facilitated by the EU High Representative Catherine Ashton. It lays the foundations for normalising relations between the two neighbours.
Two EU regulations on economic governance in the euro area are adopted. They are also known as the 'two-pack'. They strengthen the monitoring of the countries' public finances.
The European Parliament approves stricter safety standards for offshore oil and gas drilling. The aim is to reduce the risk of major accidents and limit the consequences if they do occur.
The European Council meets in Brussels to discuss the problems of tax evasion and tax fraud, as well as energy policies.
EU leaders meeting at the European Council in Brussels endorsed a comprehensive plan to combat youth unemployment. They also decide to open accession negotiations with Serbia, and confirm that Latvia will adopt the euro as its currency in 2014.
Croatia joins the EU, bringing the total number of member countries to 28. The EU now also has 24 official languages.
Neven Mimica, a Croat, takes up his post as member of the European Commission responsible for consumer policy.
Lithuania takes over the six-month rotating presidency of the Council of the EU.
EU foreign ministers called for an end to violence in Egypt and for all political parties to engage in a real and inclusive dialogue in order to restore the democratic process.
In his annual State of the Union address, European Commission President Barroso called on all those that care about Europe, whatever their political or ideological position, wherever they come from, to speak up for Europe.
Emily O'Reilly takes up office as European Ombudsman.
Rules creating a single supervisory mechanism for the oversight of banks and other credit institutions are adopted, thus establishing the first 'pillar' of Europe's banking union.
The European Council meets to discuss, amongst others, the digital economy and economic and social policy.