Diplomatic rank is a system of professional and social rank used in the world of diplomacy and international relations. A diplomat's rank determines many ceremonial details, such as the order of precedence at official processions, table seatings at state dinners, the person to whom diplomatic credentials should be presented, and the title by which the diplomat should be addressed.
The body of diplomats accredited to a country form the Diplomatic corps. Ambassadors have precedence over chargés, and precedence within each rank is determined by the date on which diplomatic credentials were presented. The longest-serving ambassador is the Dean of the Diplomatic Corps, who speaks for the entire diplomatic corps on matters of diplomatic privilege and protocol. In many Catholic countries, the papal nuncio is always considered the Dean of the Diplomatic Corps.
The rank of Envoy was short for "Envoy Extraordinary and Minister Plenipotentiary", and was more commonly known as Minister. For example, the Envoy Extraordinary and Minister Plenipotentiary of the United States to the French Empire was known as the "United States Minister to France" and addressed as "Monsieur le Ministre."
An Ambassador was regarded as the personal representative of his sovereign as well as his government.  Only major monarchies would exchange Ambassadors with each other, while smaller monarchies and republics only sent Ministers. Because of diplomatic reciprocity, Great Powers would only send a Minister to a smaller monarchy or a republic. For example, in the waning years of the Second French Empire, the United Kingdom sent an Ambassador to Paris, while Sweden-Norway and the United States sent Ministers. (Until 1893 Minister was the highest rank in the American diplomatic corps.)
The rule that only monarchies could send Ambassadors was more honored in the breach than the observance. This had been true even before the Congress of Vienna, as England continued to appoint ambassadors after becoming a republic in 1649. Countries that overthrew their monarchs proved to be unwilling to accept the lower rank accorded to a republic. After the Franco-Prussian War, the French Third Republic continued to send and receive ambassadors. The rule became increasingly untenable as the United States grew into a Great Power. The United States followed the French precedent in 1893 and began to exchange ambassadors with other Great Powers.
Historically, the order of precedence had been a matter of great dispute. European powers agreed that the papal nuncio and Imperial Ambassador would have precedence, but could not agree on the relative precedence of the kingdoms and smaller countries. In 1768, the French and Russian ambassadors to Great Britain even fought a duel over who had the right to sit next to the Imperial Ambassador at a court ball. After several diplomatic incidents between their ambassadors, France and Spain agreed in 1761 to let the date of arrival determine their precedence. In 1760, Portugal attempted to apply seniority to all ambassadors, but the rule was rejected by the other European courts.
The Congress of Vienna finally put an end to these disputes over precedence. After an initial attempt to divide countries into three ranks faltered on the question of which country should be in each rank, the Congress instead decided to divide diplomats into three ranks. A fourth rank was added by the Congress of Aix-la-Chapelle (1818). Each diplomatic rank had precedence over the lower ranks, and precedence within each rank was determined by the date that their credentials were presented. The papal nuncio could be given a different precedence than the other ambassadors. The Holy Roman Empire had ceased to exist in 1806, so the Austrian ambassador would accumulate seniority along with the other ambassadors.
In modern diplomatic practice, there are a number of diplomatic ranks below Ambassador. Since most missions are now headed by an ambassador, these ranks now rarely indicate a mission's (or its host nation's) relative importance, but rather reflect the diplomat's individual seniority within their own nation's diplomatic career path and in the diplomatic corps in the host nation:
The term "attaché" is used for any diplomatic agent who does not fit in the standard diplomatic ranks, often because they are not (or were not traditionally) members of the sending country's diplomatic service or foreign ministry, and were therefore only "attached" to the diplomatic mission. The most frequent use is for military attachés, but the diplomatic title may be used for any specific individual or position as required, generally related to a specific or technical field. Since administrative and technical staff benefit from only limited diplomatic immunity, some countries may routinely appoint support staff as attachés. Attaché does not, therefore, denote any rank or position (except in Soviet and post-Soviet diplomatic services, where attaché is the lowest diplomatic rank of a career diplomat). Note that many traditional functionary roles, such as press attaché or cultural attaché, are not formal titles in diplomatic practice, although they may be used as a matter of custom.
Furthermore, outside this traditional pattern of bilateral diplomacy, as a rule on a permanent residency basis (though sometimes doubling elsewhere), certain ranks and positions were created specifically for multilateral diplomacy:
Special envoys have been created ad hoc by individual countries, treaties and international organizations including the United Nations. A few examples are provided below:
Most countries worldwide have some form of internal rank, roughly parallel to the diplomatic ranks, which are used in their foreign service or civil service in general. The correspondence is not exact, however, for various reasons, including the fact that according to diplomatic usage, all Ambassadors are of equal rank, but Ambassadors of more senior rank are typically sent to more important postings. Some countries may make specific links or comparisons to military ranks.
Officers from the Department of Foreign Affairs and Trade (DFAT) are graded into four broad bands (BB1 to BB4), with the Senior Executive Service (SES Band 1 to SES Band 3) following above.
Ambassadors, High Commissioners and Consuls-General usually come from the Senior Executive Service, although in smaller posts the head of mission may be a BB4 officer. Generally speaking (and there are variation in ranking and nomenclature between posts and positions), Counsellors are represented by BB4 officers; Consuls and First and Second Secretaries are BB3 officers and Third Secretaries and Vice Consuls are BB2 officers. DFAT only posts a limited number of low-level BB1 staff abroad. In large Australian missions an SES officer who is not the head of mission could be posted with the rank of Minister.
There are six ranks in the Brazilian Ministry of External Affairs (Itamaraty):
Embaixador is the honorary dignity conceded permanently when a Minister of First Class assumes a Post overseas. It can also be a temporary assignment, when carried on by a lower-rank diplomat or Brazilian politician of high level.
Her Majesty's Diplomatic Service differentiates between officers in the "Senior Management Structure" (SMS; equivalent to the Senior Civil Service grades of the Home Civil Service) and those in the "delegated grades". SMS officers are classified into three pay-bands, and will serve in the Foreign and Commonwealth Office in London as (in descending order of seniority) Permanent Under-Secretary, Directors-General, Directors, or Heads of Department; overseas they will be Ambassadors (High Commissioners in Commonwealth countries), or Consuls-General, Deputy Heads of Mission or Counsellors for larger posts. (Deputy Heads of Mission at the historically most significant Embassies, for example those in Washington and in Paris, are known as Ministers.)
In the "delegated grades", officers are graded by number from 1 to 7; the grades are grouped into bands lettered A‑D (grades 1 and 2 are in Band A; 3 in B; 4 and 5 in C; and 6 and 7 in D). Overseas, A2 grade officers hold the title of Attache, B3‑grade officers are Third Secretaries; C4s are Second Secretaries; and C5s and D6s are First Secretaries. D7 officers are usually Deputy Heads of Mission in medium-sized posts or Heads of Mission in small posts.
The following ranks are used in the Egyptian Ministry of Foreign Affairs:
There are four ranks in the French Diplomatic Service: (in ascending order)
In Italy, ranks and functions are not exactly connected: each rank can cover several functions. Moreover, several exceptions apply.
People who hold the rank of Ambassador are about 30. Therefore, most of the about 150 Italian embassies or permanent representations are held by a Minister Plenipotentiary: traditionally, ambassadors are appointed to most important representations, such as London, Paris, Washington, New Delhi and Peking embassies and representations to the UN in New York City and the EU in Brussels.
After the merger of the Consular and Diplomatic Corps, the current eight grades of Spanish career diplomats are (in ascending order):
In the United States Foreign Service, the personnel system under which most U.S. diplomatic personnel are assigned, a system of personal ranks is applied which roughly corresponds to these diplomatic ranks. Personal ranks are differentiated as "Senior Foreign Service" (SFS) or "Member of the Foreign Service". Officers at these ranks may serve as ambassadors and occupy the most senior positions in diplomatic missions. The SFS ranks, in order from highest to lowest, are:
|SFS rank||Equivalent military rank||Notes|
|Career Ambassador (FE-CA)||Four-star rank (O-10)||Awarded to career diplomats with extensive and distinguished service|
|Career Minister (FE-CM)||Three-star rank (O-9)||The highest regular senior rank|
|Minister Counselor (FE-MC)||Two-star rank (O-8)|
|Counselor (FE-OC)||One-star rank (O-7)|
Members of the Foreign Service consist of five groups, including Foreign Service Officers and Foreign Service Specialists. Like officers in the U.S. military, Foreign Service Officers are members of the Foreign Service who are commissioned by the President. As with Warrant Officers in the U.S. military, Foreign Service Specialists are technical leaders and experts, commissioned not by the President but by the Secretary of State. Ranks descend from the highest, FS‑1, equivalent to a full Colonel in the military, to FS‑9, the lowest rank in the U.S. Foreign Service personnel system. (Most entry-level Foreign Service members begin at the FS‑5 or FS‑6 level.) Personal rank is distinct from and should not be confused with the diplomatic or consular rank assigned at the time of appointment to a particular diplomatic or consular mission.
In a large mission, several Senior Diplomats may serve under the Ambassador as Minister-Counselors, Counselors, and First Secretaries; in a small mission, a diplomat may serve as the lone Counselor of Embassy.
Formally the consular career (ranking in descending order: consul-general, consul, vice-consul, consular agent; equivalents with consular immunity limited to official acts only include honorary consul-general, honorary consul, and honorary vice-consul) forms a separate hierarchy. Many countries do not internally have a separate consular path or stream, and the meaning of "consular" responsibilities and functions will differ from country to country. Other titles, including "vice consul-general", have existed in the past. Consular titles may be used concurrently with diplomatic titles if the individual is assigned to an embassy. Diplomatic immunity is more limited for consular officials without other diplomatic accreditation, and broadly limited to immunity with respect to their official duties.
At a separate consular post, the official will have only a consular title. Officials at consular posts may therefore have consular titles, but not be involved in traditional consular activities, and actually be responsible for trade, cultural, or other matters.
Consular officers, being nominally more distant from the politically sensitive aspects of diplomacy, can more easily render a wide range of services to private citizens, enterprises, et cetera. They may be more numerous since diplomatic missions are posted only in a nation's capital, while consular officials are stationed in various other cities as well. However, it is not uncommon for individuals to be transferred from one hierarchy to the other, and for consular officials to serve in a capital carrying out strictly consular duties within the "consular section" of a diplomatic post, e.g., within an embassy. Some countries routinely provide their embassy officials with consular commissions, including those without formal consular responsibilities, since a consular commission allows the individual to legalize documents, sign certain documents, and undertake certain other necessary functions.
Depending on the practice of the individual country, "consular services" may be limited to services provided for citizens or residents of the sending country, or extended to include, for example, visa services for nationals of the host country.
Sending nations may also designate incumbents of certain positions as holding consulary authority by virtue of their office, while lacking individual accreditation, immunity and inviolability. For example, 10 U.S.C. §§ 936 and 1044a identify various U.S. military officers (and authorize the service secretaries to identify others) who hold general authority as a notary and consul of the United States for, respectively, purposes of military administration and those entitled to military legal assistance. A nation may also declare that its senior merchant sea captain in a given foreign port—or its merchant sea captains generally—has consulary authority for merchant seamen.
Those of the first class, to whom in France the title of ambassadeurs is restricted, are not merely the agents of their government, but represent their sovereign personally, and receive honours and enjoy privileges accordingly. They can be sent out only by such states as possess royal honours.
Basically, because of diplomatic protocol, a receiving state would not dispatch a representative with a higher rank than it has received, so when the U.S. sent ministers, it also received ministers, not ambassadors. ... The U.S. adjusted its ranking system in 1893 and began to send and receive ambassadors.
The 17th particular act annexed to the general treaty of Vienna, containing regulations concerning the precedence of diplomatic agents, may at first sight seem of little comparative moment: but it will not be thus regarded by those who recollect how often disputes concerning precedency among ambassadors have assumed a very serious and alarming aspect, and somewhat a strong tendency to produce hostilities. The 4th article of this act is well calculated to do away all future disputes on this head.