Western Union (alliance)
The Western Union (WU), also referred to as the Brussels Treaty Organisation (BTO), was the European military alliance established between France, the United Kingdom (UK) and the three Benelux countries (Belgium, the Netherlands, Luxembourg) in September 1948 in order to implement the Treaty of Brussels signed in March the same year. Under this treaty the signatories, referred to as the five powers, agreed to collaborate on defence as well as in political, economic and cultural fields.