United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967. This flag from his personal collection flew on President Dwight D. Eisenhower's presidential limousine. It has just 49 stars. Hawaii became the 50th state in 1959, and a new 50-star flag became official on July 4 - Independence Day - 1960.

White House vehicles are custom-built to distinguish and protect the President of the United States. This photograph shows a fringed American flag mounted to a special bracket on one of the two 1938 Cadillac presidential convertibles -- Queen Mary and Queen Elizabeth. Secret Service agents used the "queens" in motorcades, following closely behind the Presidential State Car.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967, serving five presidents. This 50-star American flag - officially adopted July 4, 1960 - is from his personal collection. It would have flown on the presidential limousines of Dwight D. Eisenhower, John F. Kennedy, and Lyndon B. Johnson.

Foreign policy was an outstanding aspect of John F. Kennedy's Cold War administration. Amid global political and military tensions, the president hosted many foreign leaders. This photograph shows Kennedy with King Hassan II of Morocco. The two statesmen met in March 1963 to discuss their nations' relationship and mutual concerns.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967, serving five presidents. This photograph from his personal collection shows a 1956 Cadillac. Ohio company O'Gara-Hess and Eisenhardt custom-built two of these convertibles -- Queen Mary II and Queen Elizabeth II -- for presidential motorcade duty. They served Presidents Eisenhower, Kennedy, and Johnson.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967, serving five presidents. This photograph from his personal collection shows a 1956 Cadillac. Ohio company O'Gara-Hess and Eisenhardt custom-built two of these convertibles -- Queen Mary II and Queen Elizabeth II -- for presidential motorcade duty. They served Presidents Eisenhower, Kennedy, and Johnson.

Foreign policy was an outstanding aspect of John F. Kennedy's Cold War administration. Amid global political and military tensions, the president hosted many foreign leaders. This photograph, taken just six weeks before Kennedy was assassinated, shows a parade for Ethiopian emperor Hail Selassie I. The two statesmen met in October 1963 to discuss their nations' relationship and mutual concerns.

In February 1963, President John F. Kennedy and Venezuelan President Romulo Betancourt waved to onlookers lining the streets of Washington, D.C. The two ride in the 1961 Lincoln Continental Presidential Limousine. The vehicle would be radically changed after President Kennedy's assassination. A permanent roof, bullet-proof glass, and extensive armor-plating made the car much more secure.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967. This flag of Pakistan is from his personal collection. It flew on President Dwight D. Eisenhower's presidential limousine during an eleven-nation goodwill tour in December 1959.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967. This flag from his personal collection flew on John F. Kennedy's presidential limousine during a visit from President Carlos Julio Arosemena Monroy of Ecuador in July 1962.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967, serving five presidents. This photograph from his personal collection shows President Dwight D. Eisenhower's motorcade during a 1960 visit to South Korea. Agent Gies is driving the follow-up car directly behind the President's preferred 1950 Lincoln "Bubble-top" limousine.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967. This flag from his personal collection flew on Harry S. Truman's presidential limousine during an October 1951 visit from Princess Elizabeth (later Queen Elizabeth II) of the United Kingdom.

United States Secret Service agent Morgan L. Gies was responsible for White House vehicles from 1941 to 1967. This American flag from his personal collection flew on the presidential limousines of both Franklin D. Roosevelt and Harry S. Truman. Its 48 stars represent the United States of America before the admission of Alaska and Hawaii in 1959.

In the course of Princess Elizabeth's first royal visit to Canada in October 1951, the future queen of the United Kingdom met for a short time with President Harry S. Truman in Washington, D.C. This photograph taken during their visit shows the two leaders in the back of the 1950 Lincoln presidential limousine.