Original: NATO comprises twenty-eight members : Albania , Belgium , Bulgaria , Canada , Croatia , the Czech Republic , Denmark , Estonia , France , Germany , Greece , Hungary , Iceland , Italy , Latvia , Lithuania , Luxembourg , the Netherlands , Norway , Poland , Portugal , Romania , Slovakia , Slovenia , Spain , Turkey , the United Kingdom , and the United States .
Simplified: History Its members in the beginning were : The United States , Belgium , the Netherlands , Luxembourg , France , the United Kingdom , Canada , Portugal , Italy , Norway , Denmark and Iceland .