After years of ratification struggles, including rejected referendums in France, the Netherlands, and initially Ireland, the Treaty of Lisbon took effect across the European Union. It streamlined decision-making, expanded the powers of the European Parliament, gave legal force to the Charter of Fundamental Rights, and created new leadership roles intended to give the EU a more coherent voice on the world stage.
The Lisbon Treaty was essentially a rescue mission. It salvaged much of the substance of the failed 2004 EU Constitution, which French and Dutch voters had rejected in referendums, by repackaging the same reforms into a treaty amending existing agreements rather than a single constitutional document — a move critics called a legal sleight of hand designed to avoid further referendums.
Ireland, the only country required by its constitution to hold a popular vote, initially rejected the treaty in 2008. After securing guarantees on issues like military neutrality and taxation, Irish voters approved it in a second referendum in October 2009, clearing the final hurdle.
The treaty's most visible legacy was institutional: Herman Van Rompuy became the first permanent President of the European Council, and Catherine Ashton the first High Representative for Foreign Affairs. Supporters hoped these roles would end the EU's habit of speaking with 27 different voices; critics saw them as unelected bureaucratic creep. Either way, Lisbon became the operating framework for an EU navigating the euro crisis, Brexit, and beyond.