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Office of the Historian

Principal Officers and Chiefs of Mission

Note: The information presented here is for historical research and is not necessarily up-to-date. The Department of State maintains a list of current Senior Officials and Chiefs of Mission.


This online resource continues a 1991 publication of the Office of the Historian, Principal Officers of the Department of State and United States Chiefs of Mission. Our intent is to document the history of U.S. representation abroad and the chief policymakers in the Department of State. To that end, we have provided a chronological listing of principal officers—essentially all Department officers at the level of assistant secretary or above—and chiefs of mission. (See below for a discussion of the term, “chief of mission.”) These two categories require Presidential or Secretarial designation, and, in some cases, the approval of the Senate. We have made an attempt to comprehensively list all people selected for these positions, even if they were not approved by the Senate, died before taking office, declined the position, or were otherwise unable to serve. For that reason, the pages which list our chiefs of mission by country are split into two categories: “Chiefs of Mission” lists those who held the office, and “Other Nominees” lists those who did not.

Positions Included

This database includes officers of the Department who were presidential appointees (appointed by the President with the advice and consent of the Senate) and chiefs of bureaus who hold rank equivalent to Assistant Secretary of State. These include: Secretaries, Deputy Secretaries, Under Secretaries, Deputy Under Secretaries, Assistant Secretaries, Counselors, Legal Advisers, Chiefs of Protocol, and certain administrators.

Other positions have, from time to time, been included in the database based on their particular circumstances. The complete lists of heads of the United States Information Agency, for example, are included. USIA was incorporated into the Department in 1999. Other chiefs of mission of particular historical interest have also been included.

Positions Excluded

This database does not include representatives, personal representatives, or special representatives of the President or Department of State; chargés d’affaires or chargés d’affaires ad interim (except under certain circumstances); individuals holding diplomatic commissions jointly with other representatives; special agents and other individuals on special missions; high commissioners; chiefs of mission in charge of special economic or aid missions; liaison officers; military governors or commanding officers of occupying forces or their political advisers; delegates to international conferences; or consular officers who held only consular commissions.

What is a Chief of Mission?

According to the Foreign Affairs Act of 1980 (Public Law 96-465, Section 102(3) (22 U.S.C. 3902)) a Chief of Mission is “The principal officer in charge of a diplomatic mission of the United States or of a United States office abroad which is designated by the Secretary of State as diplomatic in nature, including any individual assigned under section 502(c) to be temporarily in charge of such a mission or office.”

The Chief of Mission is often – but not always – an Ambassador. There are currently three classes of diplomatic representation established by the 1961 Vienna Convention on Diplomatic Relations, Article 14: ambassador or nuncio (accredited to the Head of State); envoy, minister, or internuncio (accredited to the Head of State); and chargé d’affaires (accredited to the Minister of Foreign Affairs). These classes have a much longer lineage. Although not a signatory, the United States followed Annex 17 to the Congress Treaty of Vienna (March 19, 1815) which established rank and precedence of diplomatic agents (ambassadors, envoys, and chargés d’affaires). The Proces-Verbal of the Conference of Aix-la-Chapelle (November 9, 1818), recognized ministers resident as an intermediate class between Ministers and chargés d’affaires.

The United States first used the rank of Ambassador in 1893, when Thomas F. Bayard was appointed Ambassador to Great Britain on March 30 of that year.

A “chargé d’affaires ad interim” refers to a diplomat temporarily acting for an absent chief of mission. This database tracks all chargé d’affaires and chargé d’affaires ad interim who served (1) for a continuous period of 12 months or more, (2) at the establishment or ending of diplomatic relations with a country, or (3) at the closure or opening of an embassy.

Database Contents

The type of information for each entry included varies based on the type of position. Entries will have some or all of these pieces of information:

When possible, the full name of the appointee has been included.
Years of birth and death
State of residency
The appointee’s state or territory of legal residence at the time of the appointment is taken from the commission, nomination, or a contemporary official record of legal residence. If the residence was omitted from these sources, the entry does not appear. Some officers changed their legal residence during their careers; in such cases the entry for their various appointments reflects the change in residence.
Career status (in the Foreign Service)
Appointees are not categorized as “career” or “non-career” before the passage of the Foreign Service Act of February 5, 1915, which restructured the Diplomatic and Consular Services. For Chiefs of Mission holding office at that date, an asterisk by their names in the alphabetical listing denotes those who were at the time of appointment (or who had previously been for at least five years) Foreign Service officers, Foreign Service information officers, or career officers in the Diplomatic or Consular Services. The asterisk also indicates those few individuals who served as diplomatic secretaries, who had then been commissioned before as Chiefs of Mission or as Presidential appointees in the Department of State, who were not serving as Chiefs of Mission in February 1915, but who were subsequently appointed or reappointed as such. All other appointees have no asterisk, even though they may have been career officers in the civil or military services. Career status reflects an individual’s status at the time of appointment. For example, Richard Holbrooke served in the Foreign Service, but was not a career member of the Foreign Service when appointed to his various positions, so he is listed as “non-career.”
Dates of service
These dates are included on a position-by-position basis. Principal officers of the Department who are presidential appointees have a date of appointment, date of entry on duty, and date of termination of appointment. An effort has been made to fix a date for the termination of the diplomatic mission of each representative vis-à-vis the host government and to describe briefly in each individual case (and as precisely as sometimes incomplete records permit) what action or event brought the mission to either a formal or a de facto close. In the nineteenth century it was customary for a Chief of Mission to present his own letter of recall; in current practice most missions terminate in actual fact with the departure of the Ambassador from his post. In all periods there have been special circumstances (e.g., death, declaration of war, severance of diplomatic relations) which have brought some diplomatic missions to an end. It should be emphasized that the effective date of a Chief of Mission's resignation frequently does not coincide with the date shown here for the termination of his or her mission abroad. For those who were designated by the Secretary, the date of appointment is the same as the date of entry on duty. For chargés d’affaires ad interim, dates of service are listed from and to the nearest month.

Key Terms

The date of appointment is that which appears upon the face of the Presidential commission issued to the appointee. It is frequently referred to as the date of commissioning or the date of attestation. Recess appointments are valid only until the end of the current session of the Senate. If the President wishes to keep a recess appointee in office, the President must re-nominate the appointee.
A document attesting that the appointee has been appointed as a principal officer of the Department or as a Chief of Mission. It is signed by the President and the Secretary of State and bears the impression of the Great Seal of the United States. “Commission” always connotes Presidential action.
This term covers chiefs of bureaus of the Department who are selected by the Secretary of State. Article II, Section 2 of the Constitution states that “the Congress may by law vest the appointment of such inferior Officers, as they think proper, in the President alone, in the Courts of Law, or in the Heads of Departments.” “Designation” always connotes Secretarial action.
This is the date that the President sends to the Senate the name of a person whom he wishes to appoint to a high-level position. Article II, Section 2 of the Constitution states that the President, “by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other public Ministers and Consuls, Judges of the supreme Court, and all other Officers of the United States, whose appointments are not herein otherwise provided for, and which shall be established by Law.” Per Senate Rule XXXI, “Nominations that are not confirmed or rejected are returned to the President at the end of a session or when the Senate adjourns or recesses for more than 30 days.”

Steps in Appointment

Nomination is the first step in the appointment process. The President submits the name of the person to be appointed to a high-level position to the Senate for approval by first the Foreign Relations Committee and then by the full Senate. Approval by the full Senate is called “Confirmation.” The appointee is then commissioned. After taking the oath of office, he or she enters on duty. Ambassadors, however, are considered to have entered on duty when they present their credentials to their host governments.