In the scene immediately following Ike and Monty's meeting on the train, after Monty is walking away along the tracks, Tex receives a teletype message of apology from Monty while Monty's voice is heard reciting the text of the message. Tex is wearing major's insignia and Ike is wearing three stars. There is a map of a shoreline above the teletype machine, possibly North Africa, and there is a Operation Torch sign on the map behind Ike. The scene is obviously related to Operation Torch, not European operations.
Immediately following the scene where Ike (Robert Duvall), traveling with General George S. Patton (portrayed by Darren McGavin), in Patton's command car, steps out of the car, and is seen physically taking a step across the German border, after saying "It's been a long, long time since an Eisenhower returned to Germany," an on screen caption states "Ohrdruf, Germany April 13, 1944." Ohrdruf is a small town in south central Germany, the infamous site of the Ohrdruf forced labor and concentration camp, a subcamp of the Buchenwald concentration camp, and famously was the first concentration camp liberated by U.S. troops, specifically the 4th Armored Division of Patton's Third Army, and was visited in person by Eisenhower, Patton, and Omar Bradley April 12-13, 1945. This was ten months and six days after D-Day (June 6, 1944). The on-screen caption is correct as to the location, but incorrect as to the date, since it could not have happened on April 13, 1944, which would have been almost two months before D-Day.
According to the cast list, Wolfgang Preiss plays Field-Marshal Alfred Jodl. Jodl was actually a Generaloberst - one rank below Field Marshal.
The transport for Gen. Giraud's flight to Gibraltar in Nov 1942 is shown as an RAF Avro York. The York was still in early prototype at that time so would not have been in military service; certainly, no-one would have risked flying generals about in one. Also, the colour scheme (all-silver) is wrong for the era. Giraud was actually taken to Gibraltar by submarine.
The aircraft shown being used as Gen. Montgomery's transport in N Africa is a Stinson L-1 Vigilant in RAF colours. It is appropriate to the era, and, although an American aircraft, some were used by the RAF - though they would have had an alphanumeric registration code on the rear fuselage, which this one lacks.
The cast list includes the character 'Gen. Arthur Tedder'. At the end of WW2, Tedder was promoted from air marshal to air chief marshal. The rank of general does not exist in the RAF.
When Ike tells Kay that Roosevelt will let her into the US Army and still owe allegiance to a foreign flag, and says she's the first person in history to be allowed to do that. During the Civil War citizens from several countries came to the US to fight for both sides while still remaining citizens of their home countries.