What did the U.K. government do on March 29?
The U.K.’s envoy to the European Union hand-delivered a letter from Prime Minister Theresa May to the office of the European Council president in Brussels, invoking Article 50 of the Lisbon Treaty and formally beginning the process of talks over the U.K.’s separation from the European Union—the process that’s come to be known as Brexit.
How did we get here?
On June 23, 2016, Britons stunned Europe’s political establishment and voted 52 percent to 48 percent to leave the European Union. Prime Minister David Cameron, who had supported the U.K.’s continued membership in the bloc and who also wanted to give voters a voice on EU membership, resigned. After a brief period of political backstabbing, which saw all the favored successors to Cameron fail in their leadership bids, Theresa May, who had also supported remaining in the EU, emerged as the U.K.’s new prime minister. She pledged to respect the wishes of the public—dashing the expectations of those who’d hoped for a change of mind. She said she’d invoke Article 50 of the Lisbon Treaty, the mechanism by which negotiations on the U.K.’s exit from the EU can begin, in March 2017. But while British politicians and policymakers argued with their European counterparts on what a future U.K.-EU relationship would look like, the U.K. High Court ruled last November the government does not have the authority to invoke Article 50, saying that authority lay with Parliament. The government appealed to the Supreme Court, which agreed with the lower court’s ruling. After weeks of heated back-and-forth in Parliament, lawmakers voted on March 13 to give the government the authority to trigger Article 50. Three days later, the measure received royal assent from Queen Elizabeth II. On March 29, May invoked Article 50.