It was President Franklin D. Roosevelt who invited the British Royal Family to visit the U.S. in light of the impending outbreak of World War II.
At the time of King George's visit, Germany had already seized control of Austria. President Roosevelt hoped that the visit would strengthen ties and garner support for the U.S. to aid in the war as allies.
The visit by the British king was significant as no reigning monarch had ever set foot on American soil.
The Americans gave the heartiest of welcomes to both King George VI and his wife, Queen Elizabeth (the mother of the present Queen Elizabeth II).
According to the Franklin D. Roosevelt Presidential Library, every minute of the Royal Visit was planned so that the king could receive the sympathy and support of the American people.
The royal couple mainly visited Washington D.C. and New York City. They were given all the privileges of a state visit including a reception at the British embassy and dining at the White House.
Out of the five-day visit, two days were also spent informally as they stayed with the Roosevelts in Hyde Park, New York. They were treated to an informal picnic and were served hot dogs by the Roosevelts.
The first visit by the King and Queen of England to the U.S. was deemed a success and thereafter set a precedent for warm relations between the two countries.