It is generally thought in the Army that Winters deserved a Medal of Honor for his attack at Brecourt Manor instead of the Distinguished Service Cross, but there was another Medal of Honor given in another D-Day action and there was a concern about giving out too many.
It is implied that Ron Spiers killed the German POW's on D-Day. The actual facts about this story remain unknown. It is reported that this event happened on D-Day, outside of Carentan, and in Bastogne. The number of soldiers killed is not known either. The only person who knows is Ronald Speirs (the correct spelling of his surname) himself, and he died in 2007.
The scene where Don Malarkey runs out into heavy fire to retrieve what he thought was a Luger pistol did actually happen according to Ambrose's book. The object Malarkey picks up is not any type of pistol but was a sighting device for one of the 105 guns taken out in the mission.
After Lt Winters tells Sgt Guarnere, "Sergeant, I'm not a Quaker!" and then leaves to a burst of laughter, Guarnere comments, "Being from Lancaster County, he's probably a Mennonite." In his memoirs, written a few years after the release of this miniseries, Winters mentions that his ancestry actually was Mennonite although his immediate family were not firm practitioners of the religion.
The battle of Brecourt Manor takes place over about 15 minutes, however in reality it lasted about three hours. The only two soldiers shown to be killed are 'John Hall' and an unnamed Warrant Officer (Andrew Hill), while in reality - as Dick Winters states in his memoir - there were four dead and six wounded.