Just as a passport represents national sovereignty—it is one of the defining categories of a claim to statehood—so harmonizing passports is a sign of cooperation. That can be a slow process. It took the nine members of the-then European Community (now the 27-strong European Union) years to settle on the color of the passport cover that its member states now share. In 1976, a year after a uniform passport was first proposed, Britain shuddered at the suggested shade of delicate lilac. Diplomats then spent four years dismissing maroon and then purple before reaching a wine-colored consensus in 1981. America's first passport cover, in 1918, was beige, going green three years later. It changed to various shades of red in 1926 and back to green in 1941. Only on the bicentenary in 1976 did it turn blue, matching the shade in the American flag. The common color was supposed to make European passports instantly recognizable. But since colors cannot be patented, nothing stops others with the same idea. Some countries that hoped to join the EU quickly adopted the right color of passport as a branding exercise. In South America the Andean Community, which once had EU-like aspirations, also favors wine-colored passports. Mercosur and Caricom, two other regional groupings, favor an American-style dark blue. Countries commonly pick colors that reflect their culture or religion, says Claire Burrows of De La Rue, a British company that has been making passports since 1915. Islamic countries often have green passport covers (though Germany's passport used to be that color, as are those of members of the Economic Community of West African States). According to Bill Waldron of Holliston, a Tennessee-based firm that prints documents for 65 of the world's 249 passport-issuing entities, darker colors are popular because they show dirt less, heighten the contrast with the crest and look more official—much as police wear dark uniforms. Interpol—one of a handful of international organizations with passport-issuing powers—provides evidence for that theory: its new travel document is black. The UN's passport, like the helmets of its peacekeeping force, is a pacific blue. Fun-colored passports exist too. But they can sometimes seem a punishment: Sweden and the Netherlands issue emergency travel documents for nationals who have lost their passports. They are pink.