North Atlantic Treaty

Four deposits complete the treaty

On 24 August 1949, Denmark, France, Italy and Portugal deposited their instruments of ratification with the United States, satisfying the treaty's remaining requirements under Article 11.

The North Atlantic Treaty consequently entered into force for all twelve original parties: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom and the United States.

The treaty made the United States its depositary — ratifications were filed with the U.S. government, which notified the other parties.

A ten-minute ceremony in Washington

President Harry S. Truman took part in an entry-into-force ceremony at 12:30 p.m. and issued a statement shortly afterwards; his calendar allowed ten minutes between them.

The twelve governments had signed the treaty in Washington on 4 April 1949. That was signature; this was legal effect.

An alliance without a command

The treaty existed on paper before it had an integrated commander or a permanent military headquarters. It was not dormant, though: the first North Atlantic Council met on 17 September 1949 and created a Defence Committee, a Military Committee, a Standing Group and five Regional Planning Groups.

SHAPE came later — activated on 2 April 1951 as the headquarters of Allied Command Europe.

Article 5 does not automatically oblige every ally to declare war; each promises to take the action it deems necessary, potentially including armed force.