Communication is an essential part of human existence. Man is a social animal and needs to express his thoughts. It was easy to communicate in person with any individual but to communicate with a person at a long distance was difficult. This difficulty gave birth to the most brilliant idea of all time-Letters, which were basically, short messages written on paper.
These letters were first delivered by pigeons or birds but gradual messengers started delivering letters on foot or horseback. This system was very expensive; hence it was only available for the royal and noble class. In the middle of 1800s the first postal stamp came into existence and mail services were made cheaper for the general population.
These growing postal services demanded the co-operation of all countries with frequent mail network. On 15 September 1875, Heinrich Von Stephan, a senior postal officer of the North Germany Confederation, opened a conference in Berne, Switzerland with the delegation from 22 countries. This meet gave birth to the General Postal Union which later on changed to the Universal Postal Union in 1878.
In 1969, the 16th Universal Postal Union Congress was held in Japan where it was decided that October 9th of each year would be celebrated as the World Post Day and the week adjoining to be celebrated as World Post Week.
In India, 9th October is celebrated as the National Post Day and October 9 to 14 is observed as National Post Week.