U.K. citizens last had blue passports in 1998. Between then and now, they have had burgundy colored passports, as have all other members of the EU.

Manufacturing the new blue colored passports has been Gemalto, a company based in Poland and run by people from France and the Netherlands. Gemalto won the contract in 2018.

More than 80 other countries, including the United States, issue their citizens blue colored passports.

At 11 p.m. GMT on January 31, the U.K. left the EU, ending a relationship that began in 1973. It was midnight in Brussels, headquarters of the EU, when the Withdrawal Agreement took effect, having been ratified by the European Council as a last formal step, following approval by the U.K. Parliament and the European Parliament.

To mark the moment, workers at EU headquarters removed the Union Flag from its displays. Also marking the moment was U.K. Prime Minister Boris Johnson, the third leader of the country to have grappled with the demands of Brexit since it was triggered by the results of a 2015 referendum. Johnson gave a speech in which he called for calm and common purpose. Meanwhile, proponents of Brexit celebrated their long-awaited moment.

In the nearly four years since the referendum, debates on the issue have been sustained and fierce, with families and friends often supporting opposing sides, for different reasons. Many in the U.K. and in other European countries had become impatient at the length of time the process was taking. On many elements of the issue still–immigration, jobs, trade–what comes next is not entirely clear.