Association football is the world's most popular sport and is worth US$600 billion worldwide. By the end of the 20th century it was played by over 250 million players in over 200 countries. Around the world, the sport is played at a professional level by professional footballers, and millions of people regularly go to football stadiums to follow their favourite football teams, while billions more watch the sport on television or on the internet. Football has the highest global television audience in sport. The sport had amateur origins and evolved into the modern professional competition.

Home Scots v Anglo-Scots was an annual association football trial match organised by the Scottish Football Association between the 1890s and 1920s to examine the abilities of possible players for upcoming full British Home Championship internationals, primarily the 'Auld Enemy' England v Scotland fixture. Selection trials were commonplace among football federations, but this match was unusual in that its regular format consisted of players based in one country facing a selection of those who had moved to another country, in order to form a combined team to oppose that other country's natives in international play.