Sam Elliott became so close to the real Basil L. Plumley and his family that during Plumley's funeral with military honors Elliott sat in the front row beside Plumley's daughter as she received the folded flag.
The real Harold G. Moore and Joseph Lee Galloway traveled back to Vietnam after the war and met the real Nguyen Huu An as part of their research for their book so they could understand the battle strategy of the North Vietnamese at Ia Drang. Moore claimed he and An had no bitterness and respected each other as soldiers.
The real Joseph Lee Galloway stepped out of the movie theater during a scene, but still approved the film. His explanation was "That was my nightmare for 36 years. I don't want to see it again."
One of the real-life officers who survived the battle was Lieutenant Rick Rescorla, who is the main figure on the cover of General Moore's book, on which the movie was based. A biography of Mr. Rescorla's very interesting life was published in the mid 2000s, called "Heart of a soldier." He died in the 9/11 attacks, while employed as Head of Security for Morgan Stanley, while making sure all of the company's employees had gotten out of the World Trade Center (they had).
Some Vietnamese actors in the movie had actually been in the North Vietnamese Army.