33¢ NATO 50th Anniversary
Issue Date: October 13, 1999
City: Brussels, Belgium
Printed By: Ashton-Potter (USA) Ltd
Printing Method: Lithographed
The issue of this stamp celebrating the 50th anniversary of the formation of the North Atlantic Treaty Organization was delayed due to the NATO-led Operation Allied Force, which involved air strikes staged against Yugoslavia.
Originally scheduled for release in April, the stamp was issued to the public on October 13, 1999. Microprinting on the stamp, found along the underside of one leaf from the branch carried by the dove, spells "UNITY." This microprinting is upside down in comparison to the rest of the design.
The North Atlantic Treaty was signed April 4, 1949, by foreign ministers from the United States and 11 other nations. NATO is credited with creating greater international stability.
Interestingly, the NATO stamp was sold before the issue date for the stamp was set by the U.S. Postal Service. Examples were found on postally used covers as well as in mint condition.