Documents and personal letters from world leaders provide a glimpse of the back drop to key historical events and a new exhibit highlights several from the defining event of the 20th century -- World War Two.

In conjunction with the Museum of World War Two, a private collection of artifacts outside Boston, and coinciding with the release of the book World War II: Saving the Reality, the exhibit at New York's Kenneth Rendell Gallery marks the 70th anniversary of the Nazi invasion of Poland and the beginning of the war.

Kenneth W. Rendell, 67, the gallery owner, author of the book and founder of the museum, has spent a lifetime collecting the letters and documents that reflect the leaders on all sides who were responsible for the dislocation of millions, and shaped the world as we know it today.

The museum is full of ghosts, said Rendell. I keep these people alive

Exhibit documents include Nazi leader Adolf Hitler's order that Berlin be defended to the last man, as well as a letter from Otto Frank in which he expresses hope that his daughter's diary might be a success and Anne Frank be remembered.

Evil fascinates people, said Rendell, who once helped expose purported diaries of Hitler as fakes.

Other documents include British Prime Minister Winston Churchill's never sent admonishment to the French president after British forces sent to bolster French troops were overwhelmed by superior German forces.

You have no right to ask us to deprive ourselves of the sole means of continuing the war by casting away in a single battle the already small forces upon which we rely as the sole sure hope of ultimate victory to us both, Churchill wrote in the original text of a June 1940 communique after British and allied forces were evacuated back to England.

The words were later removed and the letter toned down.

Also on display are letters and documents relating to U.S. President Franklin Delano Roosevelt, his wife Eleanor Roosevelt and U.S. President Harry S. Truman, who gave the order to drop atomic bombs on Japan which ended the war.

There are also letters and documents from U.S. Generals Dwight D. Eisenhower and George Patton, British General Bernard Montgomery, German General Irwin Rommel, Italian leader Benito Mussolini, Chinese communist leader Mao Tse-tung, and a young U.S. naval lieutenant John F. Kennedy requesting a transfer from Florida to the South Pacific

It is requested that I be reassigned to a Motor Torpedo Boat Squadron now operating in the South Pacific, Kennedy asked simply in February, 1943.

The artifacts are valued in the hundreds of thousands of dollars but given they can never be replaced are priceless.

Rendell calls his collection quite a journey and said while 50 years ago there was a lot of material available that could be purchased from the original owners, anything purchased now must be carefully vetted with no breaks in its known whereabouts from the time it came into being.

Of the use of his personal financial resources to fund the museum and his collection, Rendell said:

War proves the futility of it all. In World War Two, everybody lost. Japan, Germany and Italy were destroyed.

The exhibit runs from Sept 18 to Oct 1.