Football is the world's most popular sport, and the shirts worn by teams and their supporters are its greatest means of cultural expression. Every year clubs launch new kits with increasingly extravagant marketing campaigns and convoluted explanations of how their designs reflect their history and local community. But football shirts are much more than just a symbol of which club we support. A seemingly innocuous combination of colours, sponsor logos and materials can all reflect the social values, financial struggles and political ideologies of the day, as geopolitical issues increasingly seep into every aspect of the game. Investigative journalist Joey D'Urso has travelled across the globe, combining on-the-ground reporting with unparalleled analysis to collate a list of the twenty-two football shirts that best explain the modern world.