Theresa May

May became Prime Minister of the United Kingdom after David Cameron's resignation following the Brexit referendum. She was the second female prime minister after Margaret Thatcher and faced the challenge of implementing Brexit.

May formally triggered Article 50 of the Treaty on European Union, beginning the two-year process of the UK's withdrawal from the EU. This was a historic step, initiating the formal Brexit negotiations.

May called a snap general election, hoping to strengthen her majority for Brexit negotiations. The election resulted in a hung parliament, with the Conservatives losing their majority, a major political miscalculation.

May negotiated a Withdrawal Agreement with the European Union, including the controversial Northern Ireland backstop. The agreement was rejected three times by the House of Commons, leading to a political deadlock.

May resigned as prime minister after failing to get her Brexit deal through Parliament. She acknowledged that she had done her best but that it was time for a new leader to take forward the Brexit process.