Character mistake: Bucky says he read The Hobbit in 1937 when it first came out. But in 1937 he was still living in New York, and The Hobbit was only available in the UK at that time, with fairly limited numbers printed. It wasn't available in America until 1938.
Factual error: Walker has captain bars on his chest but is wearing lieutenant rank on his headgear in the photo. He is also missing the US Army tag on his uniform. Regardless of his actual rank at the time of the photo, the mix and match of rank and the missing Army tag would have been caught long before that picture was taken, especially with his friend in the photo being a sergeant major that catches uniform mistakes like that for a living. (00:34:58)