Factual error: When the action moves to England after the failed award ceremony, the British Union Flag hanging from the wall is upside down. The broad white band should be at the top left (nearest the top of the flag pole).
Factual error: In the section during the movie reel, there is footage of the 1939 world's fair in New York. The Unisphere is shown. Unfortunately, the Unisphere was constructed in 1964 for the 1964-1965 world's fair. The Perisphere (and Trylon) were the centerpiece of the 1939 fair. The Perisphere was a sphere 200 feet in diameter. The Unisphere is still standing in flushing meadows park in New York city.
Factual error: In the scenes set outside the Hydra bases, the tracked armoured personnel carriers seen are FV432s. These vehicles entered service with the British army in the 1960s, and thus were never even seen during WW2 when the film is set.
Factual error: In the closing credits, during the montage of World War II posters, the American flag appears wrapped around a cannon barrel. The flag has 50 stars, not the then-correct 48.
Factual error: At one point the Colonel references "MI-6" which is the current British term for their intelligence service. However this terminology didn't exist until after the war. During WWII it would have been referred to as Special Operations Executive or SOE.
Factual error: The German Stielgranaten - as well as other traditional German WW II hand grenades - did not have a ring and pin like the ones the Allies used, but had a string which had to be pulled hard in order to arm them. Thus they wouldn't make such a distinct 'ping' as they do in the movie.
Factual error: The early scene in the movie theatre is in 1943. In the opening newsreel a Sherman Firefly tank is shown. This tank was not made until early 1944 [the long barrel and spherical muzzle brake are distinctive]. Even if we were to assume the tank was made earlier in the Marvel Cinematic Universe due to people like Stark working for the Allies it still would not be shown in a newsreel anyway for security reasons, with German spies and sympathizers present in the US during the war. (00:09:30)
Factual error: In the scene at the World Expo, the flags are being displayed. Next to the US flag is the Bahamian flag. The Bahamas didn't have a flag until 1973 when it gained its independence. It used the British Flag or the "Union Jack" since it was still a part of Britain. Also, the flag disappears a few seconds later.