The Centenary of the Universal Postal Union (UPU) was celebrated globally in 1974. Following an official recommendation by the UPU International Bureau, member nations around the world issued dedicated commemorative stamp sets to mark 100 years since the signing of the 1874 Treaty of Bern, which established a unified global postal network and international postal cooperation. This set of stamps with the UPU logo and graphic background was issued to commemorate this significant milestone.