The Vienna Convention is a cornerstone of modern international relations and international law and is almost universally ratified and observed;[1] it is considered one of the most successful legal instruments drafted under the United Nations.

The principle of diplomatic immunity dates back to ancient times, when Greek and Roman governments granted special status to envoys.

This basic concept has endured and continued to evolve over the centuries, remaining an important element of foreign relations up to the present day.

The present treaty on the treatment of diplomats was the outcome of a draft by the International Law Commission.

One notable aspect which arose from the 1961 treaty was the establishment of the Holy See's diplomatic immunity status with other nations.