Northern Ireland whilst not a country, is a region (sometimes reffered to as a province) of the United Kingdom. So just as England,Wales and Scotland field separate teams to represent each individual country in team sports whilst remaining part of the Union so do Northern Ireland. They are a distinct area who do not consider themselves to be part of the Republic of Ireland and as such have their own football team. George Best, someone many think was the greatest British football player ever, played for Northern Ireland.
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