Question

Who was Henry Wallace? When Did he write his letter?

Answer 1

He was the vice president to FDR and the letter I suppose you're asking for is the one he wrote in 1952 titled "Why I was wrong"

Answer 2

Henry Wallace was an American politician. He was vice president of the United States, in the middle of World War II (between 1941 and 1945), during President Franklin D. Roosevelt's administration.

He had previously been Secretary of Agriculture (1933-40) and then Secretary of Commerce (1945-46). In the presidential election of 1948, he was candidate for the Progressive Party.