Factual error: Adam, who was not born of a woman and who would have no need for an umbilical cord, has a navel. (00:09:45)
Factual error: The British carry WW-I, No 1 Lee-Enfields, and the Germans carry WW-II era British No. 4 Lee-Enfields.
Factual error: Alva and Owen go see the movie "One Way Passage", released in October 1932. The movie takes places in August, the year is not stated explicitly, but there's a wall calendar in the dining room at the boarding house (you can see it when Legate leaves, calling himself a fink) for 1934, and at the same time the date shown in the office (when Redford sits at the desk to decide who will get pink slips) is August 14, Friday, which would set the movie in 1931.
Factual error: The onlookers are eating pears in spring. Wrong time of the year for ripe pears.
Factual error: The uniforms worn by the engineering force are from the wrong era. Prior to 1941 the left arm rates had the head of the eagle pointing to the wearer's rear. Steve McQueen and the rest of the Engineering force rate eagle head is pointing forward, which is from WW2.