Map showing the five founding Member States of Western Union (WU). The Brussels Treaty establishing Western Union is signed on 17 March 1948 and enters into force on 25 August 1948.

Diese Karte illustriert die Entstehung der Westeuropäischen Union (WEU), die im Jahr 1955 an die Stelle der Westunion tritt. Im Rahmen der Pariser Verträge wird das Protokoll zur Änderung und Ergänzung des Brüsseler Vertrags aus dem Jahr 1948 am 23. Oktober 1954 in der französischen Hauptstadt unterzeichnet und tritt am 6. Mai 1955 in Kraft.

Map showing accessions to Western Union (WU) and Western European Union (WEU) and the status of their members. Established in 1954, WEU is the heir to WU, which came into being in 1948 with the signing of the Brussels Treaty. Since 30 June 2011, the WEU as such ceased to exist.

Map showing the operations conducted by Western European Union (WEU) in Iraq and the Persian Gulf between 1987 and 1991 in the context of the Iran–Iraq War and the Gulf War.

Map showing the operations led by Western European Union (WEU) from 1992 to 2001 in connection with the crises and conflicts in the Balkans.