Switzerland first served as a protective power in the 19th century, when it took care of the interests of the Kingdom of Bavaria and the Grand Duchy of Baden in France during the Franco-German War of 1870-1871. During the First World War, it also protected mandates of power. During the Second World War, Switzerland, by its neutrality, became a protective power par excellence, representing the interests of 35 states – including the great war powers – with more than 200 individual mandates. The number of terms varied between four and twenty-four between 1948 and 1973. The power of protection is designated by the sending state and must also be acceptable to the host state. It must therefore maintain diplomatic relations with both states. In times of war, the Geneva Conventions also require that the protection force be a neutral country. Responsibilities and specific agreements are agreed between the protective power, the sending state and the host country. The department of interests was born in 1965 after Rhodesia`s unilateral declaration of independence, when nine African countries severed diplomatic relations with the United Kingdom. The Protective Power of the United Kingdom informed the receiving governments that British diplomats were members of the Embassy of the Protective Power.
As a result, British diplomats maintained their diplomatic immunity and were able to remain in the former British embassy, which had been placed under the responsibility of the protective power.  Innovation was widespread after the 1967 Six Day War. Arab states allowed American diplomats to remain in their capitals as the U.S. department of interests of the respective protective power, while Israel allowed Soviet diplomats to remain in Tel Aviv as the Department of Soviet Interests of the Finnish Embassy.  Burkhalter formally informed the Saudi authorities of a request from Iran that Switzerland represented Tehran`s interests in Saudi Arabia. Given Switzerland`s good relations with the two countries and Switzerland`s interest in strengthening political stability in the region, Burkhalter also proposed to represent Riyadh`s interest in Iran through a protective power mandate. Since the institution of protection of power has not been contractually formalized, there have been disputes over the rights and duties of the protective power. During the Second Boshème War, the British Empire chose the United States as its protective power, but the Boens refused to allow the United States to transfer money from the British government to prisoners of war.
The Netherlands, which served as a protective power for the Burenrublic Republics, was also unable to reach an agreement on the exchange of the names of prisoners of war.