Earlier, if two countries had to exchange mail, they had to come to an agreement with each other known as the postal treaty. This created huge problems as a country had to get into a lot of agreements to make mail services possible.
If there was no treaty between two countries for the direct delivery of mails, senders sometimes resorted to mail forwarders who would transfer the mail through an intermediate country.
The Universal Postal Union (UPU) was established to coordinate postal policies among member nations. The Universal Postal Union was set up by the Treaty of Bern of 1874. Earlier, it was known as the General Postal Union. By joining the Universal Postal Union, each member agrees to the same terms for conducting international postal duties.
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